I'm not at all complaining, but I've read this and another page over and over looking for a step by step way to do this. I've gleaned much of probably what I need, but I found it confusing that there were lots of messages in here with related, but not the same problems. My problem is the driver's side actuator, but there are some that don't defrost, some that have a/c on different sides, and I just had trouble following it all and sorting for my specific situation. What is confusing is that some people say the job is a bear, and others say it didn't take that long. There's even a youtube video on this, but he doesn't show you how to remove the dash panel. There's some conflicting... no, confusion (for me) on just how much of the dash has to be removed. Regardless, the information is here and for that I'm grateful.
I just called the local GMC dealer to confirm the part number and just for giggles, I asked them for a price on the repair. She replied, "It will be about $700, plus we'll have to remove and recharge the freon". I knew immediately that I made the right decision to try it myself. She even went so far as to tell me that she'd had people from CarX and Pep Boys call her to ask how to do this repair. Yeah, right. Commissioned salespeople. Thanks, everyone, for this valuable resource!