This is a remix / slight tweak of this thing:
https://www.prusaprinters.org/prints/6041-raspberry-pi-4-case-3030-hanging-mount-for-prusa-m
I extended the grid pattern to make a fan guard. Small things can still get past and hit the fan, but bigger things won't damage the blades.
Also cut two slots into the case so the flat-flex cable for the rPi camera can fit through and so the GPIO pins on the rPi can be used to interface with the printer directly via a purpose built cable: https://littleredtoaster.com/products/prusa-i3-mk3-mk3s-raspberry-pi-connector
The original model seems to be modeled EXACTLY to the dimensions of a rPi, so it's very very tight fit. I would suggest scaling the print up by 1 or 2% so the rPi fits in a bit better.
The threads are modeled into the case... but wont actually work as threads unless you have an insanely detailed printer / print at an obscenely thin layer height. Printing at a .3mm layer height won't work, so you end up with a hole the screw self-taps.
The author remixed this model.