4x M3-30 screws + 4 inserts are needed.

https://cnckitchen.store/products/schraube?variant=47867092009295

+

https://cnckitchen.store/products/gewindeeinsatz-threaded-insert-m3-standard-100-stk-pcs

The connector i used: https://www.aliexpress.com/item/1005005910512284.html

For powering a Buck converter like this: https://www.aliexpress.com/item/32582982343.html should work fine.

(i am using an old power supply from an external hard drive)

I printed some in PLA, some in PETG …

Some pictures show older versions of the case.

On the final you can break out a part to reach the usb port (if you want to power it from usb)

AND dry your filament if wet and use the heat gun only for a short breeze ;-)