Well, it was either a $300 grill or a new car at this time Already talking to Vengeance about an ECS install and some other minor tweaks.
The dealership did get the GPS sorted out. They used the recommended fix of insulating the cables behind the mirror and separating the cables for GPS from PDR. Haven't had an issue in over a month with reception. That is probably my biggest disappointment that GM is not aggressively fixing this problem.