I liked the `Micro SD-card guide with bezel` by `PetrosSystems` very much, but found it a bit delicate as well as didn't easily mark the actual SDCard slot in my dark environment.
Files Incude .STL and .GCODE, so no need to slice. That said, I'm a total noob and your slicing skills may be better.
This thing is friction-fit by inserting the fin beneath the SDCard slot. I'd recommend inserting the left-side of fin approximately center, push in a bit, then slide full left, then finally push right-side in.
You may remix yours here: (Hint: There are plenty of groups to un-Group) https://www.tinkercad.com/things/dchH49LtfWk