I have an Acemagic S1 mini PC and wasn't thrilled with the temps on the M.2 drives, so I took the side panel off and put a 40mm x 40mm heatsink on them. The problem then was that the side panel would no longer fit, so I designed my own case from scratch in Blender. 

I will share the STL files but the 3mf file contains modifiers to only print infill without top and bottom layers where the meshes should be. Print the side vents flat with modifiers then superglue them into place.
The holes are designed to use the same screws from the original S1 case, only 4 of them are necessary to secure the board in place.
The magnets used are 6mm x 2.6mm to hold the panel. The 4 magnet holes in the main case are friction fit, the 4 in the panel require superglue to secure.

Printed in Overture PETG on Prusa MK4S with 0.4mm nozzle 0.28mm layer height