All credit for this goes to Zitruskeks! Thanks for awesome design.Check out the original here https://www.thingiverse.com/thing:3927079

All I did was delete the button and fill in the hole since it's unnecessary for a Fenrir.

This is the only design I found that didn't have the SD reader hanging down too low where it would hit the Fenrir. The default mounting position for the Fenrir causes interference with those other card reader mounts.

Use it with this SD extender or similar https://amzn.to/3ikcKhY