Backup Cam Plate Mount (US)

My father-in-law has a big truck (Ram 3500) and installed an aftermarket backup camera. Like the one at the bottom of the summary.
However, with how the rear of the truck was he couldn't find a clean spot to install the camera without getting in the way of the tailgate while still having a solid view of the hitch.

So... While they were in town visiting, I told him I'd whip something up. I printed one out of PLA to test fit then printed out of PETG for the final. He wanted to wait to see how