This is pretty specific, but I had a computer (Acer nitro 50) in which I needed to mount an additional HDD for a RAID array. So I created this mounting system which actually worked pretty well. I figured it would be easy for someone to modify the hole mounting patter for their own use if needed. Or perhaps you could use it to mount to something else. Should work with your standard big HDD.

Snapping together of the two parts is very satisfying, i'm pretty happy with it. It feels solid

I think I did print with supports which where kind of a pain to remove. Printed in PETG.