Just wanted to put this out here in case it helps anyone out.
I did the GM approved DL3 => DQS mirror upgrade today on my 2014 LTZ 1500. The RZY harness was a pain & took more time to install than both mirrors combined. At the end of the day, all mirror features still work (adjust, power fold, reverse tilt, cargo light, park lanp), except I can no longer update my mirror/seat memory profiles. The dealership I bought the mirrors from sent me a code for a BCM update, I'll have to look into that on Monday. Does anyone have more information on that? Something I can tell my local dealer besides, "this code, BCM, Mirrors, go"?