Was orignally going to use this before I decided to switch to heated bed and power supply. The AC adapter power supply is still in the BOM for the Rook, figured I share this in case someone is going that route.
It uses 2 short heat inserts, 2 M3x12mm to clamp it together and then M3x6 or 8 to mount it to the frame.
The author marked this model as their own original creation.