Here's my design files for the Let's Split V2. It's a sandwich-style case with cutouts at the back to accomodate the USB jack and the TRRS jack.

The design file has 4 top and bottom pieces and 8 middle layer pieces. This is only good for 1 whole case for 2 halves, and 1 case that has no middle layers (you'd need to use standoffs).

There's 4 different types of pieces the case uses:

• Top/Switch layer - Each half uses 1 of these
• Bottom layer - Each half uses 1 of these
• Middle layer
  • C-shaped piece - Each half uses 3 of these, use a 4th one if you need more space (like when using a Pro Micro with Mini USB jack)
  • Stick piece - Same number as the C-Shaped piece

This case was designed to use M2 screws and standoffs. The holes in the middle layers are for the standoffs, while the holes in the top and bottom layers are only wide enough for the screws.

I used Ponoko to have the case cut and used 3mm acrylic. I included the .eps file here, because when I initially sent in the .svg file, they had an issue with sizing (due to SVG export issues with Adobe Illustrator), so I had to export as .eps for them.