An RPi 3b Case that fits the Prusa Enclosure by Printed Solid (https://printedsolid.com/products/safety-enclosure-for-prusa-printers?variant=2201706332172).

The case can mount on the fan holes or on the left side holes rear of the vent/cable hole.

Top I used is direct from:
http://www.thingiverse.com/thing:922740

Bottom is a remix of:
https://www.thingiverse.com/thing:2392368

Screws:
M2x3 screws to affix RPi to case
M3x16 Cap screws to connect top/bottom of case
M3x16 (or 12/whatever) with nuts to connect case to enclosure

Print Settings:
.2 layer height
20% infill
No Supports
I used PLA