smartelleking

Revisiting an old threat, because I have been racking my brain looking through the web! So need assistance. I have a 2013 Chevy Avalanche and replaced the factory Head Unit with an OEM NAV HU. I see different websites that have plug & play wiring harnesses to reroute the original rear view mirror backup camera image to be viewed on both mirror and NAV HU but they are either for a truck or SUV. Which is needed for the actual Avalanche? I can not find anywhere that has an image to the exact location where the wiring harness would plug in on the Avalanche? Any help is appreciated