Hey all. i bought an 07 Escalde has the front nav system but not the rear entertainment sytem. i would like to install a a factory oem monitir and hook it up to my radio. i want to be able to control and send video from my front nav. i know that the harness is not available on the top of the roof console and that i have to modify the canopy. my question is that i need some schematics or wiring diagrams for the Radio/entertainment system so i can play with it or a part number for the harness for the RES