Nice Job! That looks awesome! I have been looking at a similar model for my 05 yukon. The price tag hurts a little too much right now.
Also, did you remember to turn on the backup camera in the Advent menu? It is turned off by default.
I've got a 2013 Silverado Z71 All Star edition that has the factory back up camera and bluetooth installed on it already. I saw on your later posts that the OGM1 nav screen integrates with the factory back up camera but does it integrate with the factory bluetooth system as well? I noticed that on specs for the nav screen it calls out a bluetooth interface with an external microphone. If it doesn't I don't think that would be a deal breaker since the screen looks awesome to begin with, it would just be nice to use the factory stuff.