Ford Excursion :: Location Of Reverse Wire For Backup Camera Installation?

My reverse camera goes over the mirror, its a mirror when not in use and a camera when in reverse. The way this one is set up, the camera taps switched 12 volts at the rear of the car (tapped trailer connector for these) and the video signal runs forward (ran under headliner to center console to mirror). The monitor needs 12 volts, ground, and + 12 volts when I shift into reverse. I just read a half dozen threads where people suggested tapping into a black wire with pink stripe in the driver's kick panel. Just checked, no such wire on mine. I do not want to run a wire back from the taillight, this seems backwards since the power goes from the front of the truck to the reverse light in the taillight I just need to find the right wire. I checked the reverse relay and the fuse in the fusebox and they are both 12 volts when the truck is on, so they must be prior to the reverse switch.