depends what year you have. loc pics seem to be the easiet. I have an 07 and they only seem to go back to 09 w the loc pics. 5 yr rolling manufacture cycle maybe? I found this w more than a couple suppliers.
I had to go w navtool. had to remove head unit and ship it to them for internal mods. they ship it back and then u install. comes back w a small box wired to it w 2 ground leads ( 1 is for parking brake), 1 12v accessory power lead, 12v reverse power lead, and another for a push button toggle switch(like a valet switch) to switch between vid 1, vid 2, and factory screens. vid 1 can b a forward cam or dvd in. I just got mine back and am prepping for the install. also got a factory looking cam from rearviewsafety.com it replaces the driver side license plate light but includes a light and camera in 1 small housing. that comes in tomorrow.
I have been searching posts for where to find accessory power to bring to the head unit and reverse as well. easiest?