I replaced my system this year with this:
https://www.amazon.com/Digital-Wirel...KYJJM5CJGX43PF
I ordered an extra camera that I mounted on the ladder that looks to the left at the fuel fill so I can get my position right when pulling up to the gas pumps. This camera i powered by tapping into the right tail light (parking light) so I need to turn on the parking lights to power it up. This works great.
The normal camera is powered with the original 12Vdc. I just found the power with a meter. I just cut the video wire and use the wireless cam.
The dash unit fits nicely with a 1/2 in ch on foam and Velcro. The monitor antenna is a little tricky. I drilled a hole once I was sure it was working and it sticks through the dash panel behind the monitor.
Sudsy