I don't know if I'll ever get around to actually doing this project, so I might as well share the idea.

1. Buy a
Official GeekHack Laminated Key Checking and Layout Sheet from TechKeys.us
2. Buy just the
Storage Kit Plungers - Bulk, from KeyCapsdirect.com
3. Get a drill press and using the layout sheet as a guide, drill holes into a sheet of
thin plywood. May have to use some other form of backing as well.
4. Glue the barrels into the wood.
5. Mount key caps
6. Install in shadow box.
When drilling the holes, I think you could do it with two boards at a time, so the the second board could act as a template in the future. Additionally, you could cover the board in felt, or paint it to provide a background that might appear between the key caps.
Like I said, it's an idea that I've been noodling on, but haven't had the time to actually do anything about it.
