I’ve been trying to experiment with TinkerCAD to model a 3D printable box for this project. I have the bottom of the case designed with the mounting holes for the Pi. I haven’t been able to figure out how to design the top of the case so that it snaps into place.
I have no prototyped this so I can’t even say for sure that the mounting holes are correct, but I believe they are. I did make the holes slightly smaller to allow screws to bite into the plastic.