Atari Mega ST RGBTOHDMI Rear Expansion Mount
Rear mount for RGBTOHDMI suitable for Atari Mega 2 or 4 STs, designed to fit a CPLD based RGBTOHDMI with 12-bit daughter board and using a Pi Zero 2 or Pi Zero 2 W. If you use other PIs YMMV.
Use M2 nuts and bolts to secure the Pi to the mount.
If you would like to make amendments in Onshape, my design files are linked below.