I am planning on doing this myself and have been researching and bugging other members for a while Below is a response from one of the members who have done the conversion. I hope this helps. Let us know how it went. BTW: do you have an RNS-315 or 510? Can you please post a part number for the harness?
"These are the three connections at the camera handle end of the harness. The blue and black connectors attach directly to connectors coming off the camera. The yellow wire gets tapped into the the reverse light wire. This is the trigger wire. Alternatively, you can run this wire to the CECM in connector C, pin 28, but that is a hell of a lot of work getting to the CECM.
The other end of the harness has the following connectors and wires. The big black connector here plugs into the back of the RNS-315/510. This carries the camera signal. The red wire is power, and needs to be inserted into the fuse panel in spot #16, which is the spot that it is located in in Europe. The black wire is ground, so find a ground near the fuse box and use that."