I looked at the jail break option, which would be $500 if you could get the wiring harness that goes thru the headliner. So I did my own wired camera system. I bought a wired backup camera system complete with its own monitor, off ebay for around $40. Mounted the camera on a magnetic based stand. I just attach this stand right in front of the fifth wheel hitch and watch the pin go right into the hole while I back up. Once hitched up I just pull the camera out of the bed, and store it till I need it again. Its not greatest way to do it, but I can see the hitch and pin perfectly as I hitch up. The wireless IBall camera system you see advertised might work too, but it was $150
My silverado 3500, was arranged in a manner where I was able to see the hitch and pin in the rear view mirror, on this RAM the rear headrests are higher, and the hitch sets lower in the bed...so I cant see it readily.