The 1U rackmount bracket I am using is from ebay (https://www.ebay.com/itm/264097865148) but you should be able to use any decora bracket.
The face plate named decora_rpi_3b.stl should work for the Raspberry Pi 2, but it didn’t fit the Raspberry Pi B+ I checked.
I wanted to tolerance to be pretty low, but I only have one Raspberry Pi 4b to verify with. Please let me know if you have issues.
Use four M2.5 x [4, 6, 8] if you don’t want the bolts to extend beyond the bottom of the base. I had to create the threading for M2.6 on the mounts to avoid tapping.
Print Settings
Printer Brand: Creality
Printer: Ender 3
Rafts: No
Supports: No
Resolution: 0.2 mm
Infill: 15%
Filament: Hatchbox PLA White
Notes:
All the black prints were done with Overture PLA Black (https://www.amazon.com/gp/product/B07PGY2JP1).
Credits:
ButlerTheButler