This is an adapter I made to mount my Bigtreetech SKR E3 Turbo in my Geeetech A30M case. After mounting board, Leave SD card in slot in board, and hook the USB cable to the motherboard, then run USB cable out the old USB cable side port. To get longer range I used a USB extender cable, and it works great. The mounting holes are close to being perfect.

This should work on other Geeetech models as well, along with any other board that uses the Creality hole pattern.