This is version 4 of my screw brackets for the AGS-101 mod for Game Boy Color. These work especially well with @bluishsquirrel's or @jellybellycustoms' lenses. I recommend printing these in ABS and using a plastic epoxy to glue them into place.
You can see my full installation video here: https://www.youtube.com/watch?v=aBe4gtacweY
These don't have a screw hole (I like to drill my own), but if you want these to print with a hole, Retro Modding has a version here: https://www.thingiverse.com/thing:2810909