diff --git a/docs/guide/openreliant.d.luau b/docs/guide/openreliant.d.luau
index ad8a0d27..fa9891fb 100644
--- a/docs/guide/openreliant.d.luau
+++ b/docs/guide/openreliant.d.luau
@@ -880,6 +880,8 @@ export type Hud = {
     register_display: (name: string, definition: {frame: (seconds: number) -> (), replaces: { HudInstrument }?, layout: { [HudInstrument]: HudLayout }?, parts: { [HudPart]: HudPartLayout }?}) -> string,
     --- Turns the display `name` on or off: the calling mod's by its own name, or any mod's by the qualified one. Returns whether it's registered.
     set_display_enabled: (name: string, enabled: boolean) -> boolean,
+    --- Changes where the display `name` puts the game's instruments and their parts, after it registers: the calling mod's by its own name, or any mod's by the qualified one. `layout` and `parts` replace the display's, with the checks `register_display` makes; one left out stays as it was, and a mistake changes nothing. They go back as they were as soon as the display is turned off, fails or its mod stops. Returns whether it's registered.
+    set_display_layout: (name: string, placement: {layout: { [HudInstrument]: HudLayout }?, parts: { [HudPart]: HudPartLayout }?}) -> boolean,
     --- Where the game's instrument `instrument` last drew, in the window's pixels, as the mods' displays place it, and even while one stands in for it; nil before it first draws, or outside a mission.
     bounds: (instrument: HudInstrument) -> HudBounds?,
     --- Where the part `part` of the game's instruments last drew, in the window's pixels, as the mods' displays place it, and even while one hides it; nil before it first draws, or outside a mission.
@@ -1161,6 +1163,7 @@ export type Interfaces = {
         height: number,
         register_display: (name: string, definition: {frame: (seconds: number) -> (), replaces: { HudInstrument }?, layout: { [HudInstrument]: HudLayout }?, parts: { [HudPart]: HudPartLayout }?}) -> string,
         set_display_enabled: (name: string, enabled: boolean) -> boolean,
+        set_display_layout: (name: string, placement: {layout: { [HudInstrument]: HudLayout }?, parts: { [HudPart]: HudPartLayout }?}) -> boolean,
         bounds: (instrument: HudInstrument) -> HudBounds?,
         part_bounds: (part: HudPart) -> HudBounds?,
         window_state: (instrument: HudInstrument) -> HudWindowState?,
diff --git a/docs/guide/reference.md b/docs/guide/reference.md
index 25b50e00..6dc31850 100644
--- a/docs/guide/reference.md
+++ b/docs/guide/reference.md
@@ -270,6 +270,7 @@ Drawing over the flight display, while it's shown: text, lines and rectangles, i
 | `height` | number | The window's height, in pixels. |
 | `register_display(name: string, definition: {frame: (seconds: number) -> (), replaces: { HudInstrument }?, layout: { [HudInstrument]: HudLayout }?, parts: { [HudPart]: HudPartLayout }?})` | string | Registers a display, which `name` qualified with the mod's name names. While the flight display shows, `frame` draws it with this package's functions each frame, until it's turned off with `set_display_enabled`. A failed `frame` turns off that display only. `replaces` lists the game's instruments it stands in for, which aren't drawn while it's on, `layout` moves and scales the instruments it names, and `parts` moves, scales, aligns, rewords or hides the parts of them it names; they keep working, and go back as they were as soon as it's turned off, fails or its mod stops. Returns the qualified name. |
 | `set_display_enabled(name: string, enabled: boolean)` | boolean | Turns the display `name` on or off: the calling mod's by its own name, or any mod's by the qualified one. Returns whether it's registered. |
+| `set_display_layout(name: string, placement: {layout: { [HudInstrument]: HudLayout }?, parts: { [HudPart]: HudPartLayout }?})` | boolean | Changes where the display `name` puts the game's instruments and their parts, after it registers: the calling mod's by its own name, or any mod's by the qualified one. `layout` and `parts` replace the display's, with the checks `register_display` makes; one left out stays as it was, and a mistake changes nothing. They go back as they were as soon as the display is turned off, fails or its mod stops. Returns whether it's registered. |
 | `bounds(instrument: HudInstrument)` | [HudBounds](#hudbounds), or nil | Where the game's instrument `instrument` last drew, in the window's pixels, as the mods' displays place it, and even while one stands in for it; nil before it first draws, or outside a mission. |
 | `part_bounds(part: HudPart)` | [HudBounds](#hudbounds), or nil | Where the part `part` of the game's instruments last drew, in the window's pixels, as the mods' displays place it, and even while one hides it; nil before it first draws, or outside a mission. |
 | `window_state(instrument: HudInstrument)` | [HudWindowState](#hudwindowstate), or nil | How far the game's window that holds `instrument` has opened, and whether it's opening or closing, as the display last moved it on, which it does in every view; for the comms, the further open of its two windows. Nil for an instrument outside the windows, and outside a mission. |
@@ -646,6 +647,7 @@ turret, and a turret's own scripts on their turret.
 | `height` | number | The window's height, in pixels. |
 | `register_display(name: string, definition: {frame: (seconds: number) -> (), replaces: { HudInstrument }?, layout: { [HudInstrument]: HudLayout }?, parts: { [HudPart]: HudPartLayout }?})` | string | Registers a display, which `name` qualified with the mod's name names. While the flight display shows, `frame` draws it with this package's functions each frame, until it's turned off with `set_display_enabled`. A failed `frame` turns off that display only. `replaces` lists the game's instruments it stands in for, which aren't drawn while it's on, `layout` moves and scales the instruments it names, and `parts` moves, scales, aligns, rewords or hides the parts of them it names; they keep working, and go back as they were as soon as it's turned off, fails or its mod stops. Returns the qualified name. |
 | `set_display_enabled(name: string, enabled: boolean)` | boolean | Turns the display `name` on or off: the calling mod's by its own name, or any mod's by the qualified one. Returns whether it's registered. |
+| `set_display_layout(name: string, placement: {layout: { [HudInstrument]: HudLayout }?, parts: { [HudPart]: HudPartLayout }?})` | boolean | Changes where the display `name` puts the game's instruments and their parts, after it registers: the calling mod's by its own name, or any mod's by the qualified one. `layout` and `parts` replace the display's, with the checks `register_display` makes; one left out stays as it was, and a mistake changes nothing. They go back as they were as soon as the display is turned off, fails or its mod stops. Returns whether it's registered. |
 | `bounds(instrument: HudInstrument)` | [HudBounds](#hudbounds), or nil | Where the game's instrument `instrument` last drew, in the window's pixels, as the mods' displays place it, and even while one stands in for it; nil before it first draws, or outside a mission. |
 | `part_bounds(part: HudPart)` | [HudBounds](#hudbounds), or nil | Where the part `part` of the game's instruments last drew, in the window's pixels, as the mods' displays place it, and even while one hides it; nil before it first draws, or outside a mission. |
 | `window_state(instrument: HudInstrument)` | [HudWindowState](#hudwindowstate), or nil | How far the game's window that holds `instrument` has opened, and whether it's opening or closing, as the display last moved it on, which it does in every view; for the comms, the further open of its two windows. Nil for an instrument outside the windows, and outside a mission. |
diff --git a/docs/guide/scripting.md b/docs/guide/scripting.md
index bff7ea68..70726423 100644
--- a/docs/guide/scripting.md
+++ b/docs/guide/scripting.md
@@ -1854,6 +1854,10 @@ hud.register_display("radar", {
   growing from where it stands on the screen, as the whole display grows with the window.
 - Everything goes back as it was as soon as the display is turned off, its `frame` fails, or its
   mod stops. Where two displays place the same instrument, the one registered later does.
+- `hud.set_display_layout(name, { layout = ..., parts = ... })` changes a display's `layout` and
+  `parts` after it registers, such as for a layout that follows the window's size, with the same
+  checks. Each one the table gives replaces the display's, one it leaves out stays as it was, and a
+  mistake changes nothing.
 - `hud.bounds(instrument)` gives where an instrument last drew, in the window's pixels, as the
   layouts place it, and also while a display stands in for it, so that a display can draw its own
   in the game's instrument's place.
diff --git a/src/scripting/drawing.zig b/src/scripting/drawing.zig
index ec9b33e9..ddde7ce6 100644
--- a/src/scripting/drawing.zig
+++ b/src/scripting/drawing.zig
@@ -535,6 +535,7 @@ pub fn Package(comptime which: Which) type {
                 return @import("registries.zig").show(call, .display, name, enabled);
             }
         }.set) else {};
+        pub const set_display_layout = if (which == .hud) api.Native("Changes where the display `name` puts the game's instruments and their parts, after it registers: the calling mod's by its own name, or any mod's by the qualified one. `layout` and `parts` replace the display's, with the checks `register_display` makes; one left out stays as it was, and a mistake changes nothing. They go back as they were as soon as the display is turned off, fails or its mod stops. Returns whether it's registered.", "name: string, placement: {layout: { [HudInstrument]: HudLayout }?, parts: { [HudPart]: HudPartLayout }?}", "boolean", @import("registries.zig").setLayout) else {};
         pub const replaced = if (which == .hud) instruments.replaced else {};
         pub const bounds = if (which == .hud) instruments.bounds else {};
         pub const part_bounds = if (which == .hud) instruments.part_bounds else {};
diff --git a/src/scripting/presentation.zig b/src/scripting/presentation.zig
index e5205909..a4c24369 100644
--- a/src/scripting/presentation.zig
+++ b/src/scripting/presentation.zig
@@ -753,6 +753,38 @@ test "a display stands in for the game's instruments and reads what they show" {
     fixture.shown.endGame();
 }
 
+test "a display changes its layout after it registers" {
+    var fixture: Fixture = undefined;
+    try fixture.init(&.{.{
+        "a",
+        &.{
+            .{ "mod.ini", "[Scripts]\nPlayer=player.luau\n" },
+            .{
+                "player.luau",
+                \\local hud = require("openreliant.hud")
+                \\hud.register_display("radio", {layout = {clock = {scale = 2}}, parts = {radio_face = {scale = 2}}, frame = function() end})
+                \\-- The layout follows the window, and the parts stay, as the table leaves them out.
+                \\assert(hud.set_display_layout("radio", {layout = {clock = {offset = vector.create(5, 0, 0)}}}))
+                \\-- A mistake changes nothing, and a name not registered isn't one.
+                \\assert(not pcall(hud.set_display_layout, "radio", {layout = {clock = {scale = 0}}, parts = {}}))
+                \\assert(not pcall(hud.set_display_layout, "radio", {placement = {}}))
+                \\assert(not hud.set_display_layout("b:radio", {}) and not hud.set_display_layout("nothing", {}))
+            },
+        },
+    }});
+    defer fixture.deinit();
+    try fixture.shown.startGame(null, fixture.mission.objects, false);
+    defer fixture.shown.endGame();
+    // The displays place the instruments while the flight display's layer shows.
+    var view: engine.game.camera.Camera = .{};
+    var viewing: engine.game.camera.Viewing = .{};
+    var host: Host = .{ .seconds = 0.04, .devices = &fixture.devices, .window = .{ 640, 480 }, .camera = .{ .camera = &view, .viewing = &viewing, .now = 1, .player = 0 } };
+    host.views.set(.hud, .{ .font = &fixture.font, .gpa = std.testing.allocator, .screen = .{ 640, 480 }, .scale = 1 });
+    fixture.shown.frame(host);
+    try std.testing.expectEqual(hud.Placement{ .offset = .{ 5, 0 } }, fixture.shown.instrumentPlacements().get(.clock));
+    try std.testing.expectEqual(hud.Placement{ .scale = 2 }, fixture.shown.partPlacements().get(.radio_face).place);
+}
+
 test "a display reads the cockpit's instruments in any view" {
     const gpa = std.testing.allocator;
     var fixture: Fixture = undefined;
diff --git a/src/scripting/registries.zig b/src/scripting/registries.zig
index 8544ef7f..4d5dea96 100644
--- a/src/scripting/registries.zig
+++ b/src/scripting/registries.zig
@@ -359,6 +359,43 @@ pub fn registration(comptime kind: Kind) fn (api.Call) i32 {
     }.run;
 }
 
+/// `hud.set_display_layout(name, placement)`: replaces where the display `name` puts the
+/// instruments, its `layout`, and their parts, its `parts`, with the checks `register` makes. A
+/// field the table leaves out stays as it was, and a mistake changes nothing
+/// ([#1028](https://github.com/OpenReliant/openreliant/issues/1028)).
+pub fn setLayout(call: api.Call) i32 {
+    const state = call.state;
+    _ = presentation.Presentation.of(call);
+    const name = values.read(state, []const u8, 1, "name");
+    if (state.typeOf(2) != .table) call.raise("expected a table of layout and parts", .{});
+    var buffer: [runtime.max_name]u8 = undefined;
+    const registry = &call.runtime().registries;
+    const found = if (call.named(name, &buffer)) |qualified| registry.find(.display, qualified) else null;
+    const index = found orelse {
+        state.pushBoolean(false);
+        return 1;
+    };
+    var layout = registry.entries.items[index].layout;
+    var placed_parts = registry.entries.items[index].parts;
+    state.pushNil();
+    while (state.next(2)) {
+        const key = (if (state.typeOf(-2) == .string) state.toString(-2) else null) orelse call.raise("placement keys must be names", .{});
+        if (std.mem.eql(u8, key, "layout")) {
+            layout = .initFill(null);
+            readLayout(call, &layout);
+        } else if (std.mem.eql(u8, key, "parts")) {
+            placed_parts = .initFill(null);
+            readParts(call, &placed_parts);
+        } else call.raise("unknown placement field '{s}': a display's placement has layout and parts", .{key});
+        state.pop(1);
+    }
+    const entry = &registry.entries.items[index];
+    entry.layout = layout;
+    entry.parts = placed_parts;
+    state.pushBoolean(true);
+    return 1;
+}
+
 pub fn show(call: api.Call, kind: Kind, name: ?[]const u8, enabled: bool) bool {
     _ = presentation.Presentation.of(call);
     const registry = &call.runtime().registries;