I modified the Raspberry Pi 5 case from plammers_260162, 
which allows you to install an M2 SSD adapter underneath.

To do this, I adjusted the height of the cover and 
added holes to the base plate so that
the Raspberry Pi can be screwed in from below,
e.g. with the screws included with the “RP Official M.2 HAT+”.

I have successfully used the adapter with the following HATs:

- Raspberry Pi Official M.2 HAT+ for 5
- Geekworm X1001 PCIe to M.2 NVMe Key-M SSD Shield for Raspberry Pi 5

I attached the cover with M3x30 screws.