Worked up a design for this in BlockSCAD:
including an option to lay out the parts to cut:
By golly, I think you’ve got this figured out, Will. +1
If anyone wants to experiment with it:
Naturally the next step is exporting to OpenSCAD, moving the variables and adjusting them for the Customizer and adding projection() commands where necessary:
then export SVGs and import into Carbide Create.