This is a slightly adapted version of: https://github.com/okke-formsma/dactyl-manuform-tight/
The changes I made were to the bottom plate, which fit snugly into the top part of the case. I wanted a little more room to work with, so I instead made the bottom a case fitting that you screw together. It also allows you to print it in a different material. This is nice if you want different colors, or if you want a translucent bottom so you can include underglow LEDs into your build.