This remix of Oneiro's rack mount for a Pi 5 is designed for threaded inserts (M2.5). This allows mounting of a Pi (and HAT). I used these inserts from CNC Kitchen: https://cnckitchen.store/products/gewindeeinsatz-threaded-insert-m2-5-standard-100-stk-pcs
I included the STL, OBJ and F3D files.
You can use the D, L and W parameters in the F3D file to adapt this design for M3 inserts.
The author remixed this model.
The original model relied on M3 screws to fasten the pi directly to the printed part. This Version is set up for heat set threaded inserts.