psu_usba_v_space_w = 1.7;
 psu_usba_v_space_l = 3.0;
 
+psu_test_ceil = 2.5;
+
 // ----- calculated -----
 
 psu_z = NutBox_h_base(psu_board_nutbox);
   }
 }
 
-module PsuMountDemo(ceil = 2.5) { ////toplevel
+module PsuMountDemo() { ////toplevel
+  ceil = psu_test_ceil;
+
   translate([0, psu_y, psu_z]) {
     difference(){
       PsuMountPositive();
   }
 }
 
-module PsuMountTest(ceil = 2.5) { ////toplevel
+module PsuMountTest() { ////toplevel
+  ceil = psu_test_ceil;
   $fs = 0.1;
   $fa = 3;
   difference(){
     }
   }
 }
+
+psu_multicolour_gap = 0.075;
+psu_initial_layer_thick = 0.400;
+psu_initial_layer_width = 0.750;
+psu_window_ledge = 0.50; // each side
+
+module PsuMountTestFullLayerFrame(ix) {
+  sz = psu_sz*2 + [1,1]*psu_initial_layer_width*(3+ix);
+  translate([0, psu_y]) difference(){
+    square(center=true, sz + psu_multicolour_gap*2*[1,1]);
+    square(center=true, sz);
+  }
+}
+
+
+module PsuMountTestFullMain() { ////toplevel
+  ceil = psu_test_ceil;
+
+  linextr(0, psu_initial_layer_thick)
+    PsuMountTestFullLayerFrame(0);
+  
+  difference(){
+    translate([0,0, ceil])
+      PsuMountTest();
+
+    translate([0, psu_y, 0]) {
+      linextr(-1, psu_initial_layer_thick) {
+       offset(delta=psu_window_ledge + psu_multicolour_gap)
+         PsuLedWindowsPlan();
+       offset(delta=psu_multicolour_gap)
+         PsuLedLegendsPlan();
+      }
+    }
+  }
+}