I have a 2016 model that has several USB outlets around the interior. One is located near the rear window. As far as I can tell, the wires to the USB are 12VDC. I tapped those wires to power my rearview camera. That way you do not have to have your car lights on to power the camera. I installed a little in-line switch to the camera and only hve to remember to turn it on and off. Or not. If you are on shore power, it doesn't matter.
It works fine. I elected to mount camera on the outside and threaded the wires out through the slit through which the window opening struts pass. At that point you could choose to mount the camera between the screen and the glass or just above the window.
My additional suggestion is to mount the camera dead-center. The one in my RAM 1500
is a little off center and at times makes backing into a target difficult.