Here's everything I've done as I remember and here's the riser holder .stl google docks link. And yep, I've designed it, but I was pretty limited with the printing space (Elegoo Mars) so it could be done better.This is almost exactly what i had in mind, thank you for sharing!
To clarify you're using the same GPU IO shield, but re-drilled the mounting holes? Also did you design the riser extender yourself?
Thanks for sharing again, this is super helpful.
The problem with that exact part is that it was built for that 24 mm gpu move, so you'll need to modify it slightly for different gpu offsets