So I wanted to put something in the open spot next to the USB port in the center dash. I like having always hot 12V sockets, so I decided to put 2 in there. First I ran wiring from my auxiliary fuse block into the back of the opening. I drilled a 1/2" hole in the back of the opening to run the wires through.
Then I designed a 2-socket holder that fit into the opening. I 3D printed it.
Test fit the 12V sockets:
Test fit everything into the opening:
Sanded smooth and painted low gloss black:
Used 3M double-sided automotive trim tape to hold it in place. Final install: