I know this is not the answer you are looking for....... but I wired my voyager camera to the clearance lights so when you turn on your running lights it powers up the camera that is a good power source. I installed a blank outlet cover on the inside just below the lights so I can get at the wiring.
But I am not sure if that's how they wired it at the factory??
Just my 2 cents.
2011 Ford F-350 Crew cab, short bed King Ranch 6.7 Diesel
2012 Voltage 3200 TH
2010 Polaris RZR LE