Well this just isn't as easy as anyone says it will be. The GMC dealer across the street said it will be $50 to reprogram the entire system. 1- I'm not paying $50 and 2- They're not reprogramming everything. Oh, and they can't do it until tomorrow (there were 0 cars in the service bays). He also gave me a very curious look when I said it was a 2006 but it was not a warranty issue.
Today is the 7th day to get the cores back, so I'm thinking I'll just put my stock ones back in and get a refund. Too much hassle, too many problems. Hopefully the rest of you guys have much better luck than me.