This is a remix of boksbox small panel. I needed a bigger cover and also didn't want to have to glue pieces together. Also this is adjusted for 5/8 drywall.

Simply print the 3 pieces out. You can use the inside of the back frame as a template to cut out the drywall. the backplate snaps into the frame and the cover snaps on and can be popped off with a flat head screwdriver.