Save yourself alot of hassle and get everything from Evan. If you really want it to be as good as it can get, ship it to him. His trans are no joke. I have beat the piss out of mine, over 1,100hp, and it takes it like a champ.
Pretty sure gm has it setup so, if it is on recirculate, the AC is automatically turned on. Doesn't matter wether the AC button is on or not. Go look under the hood and see if the AC compressor is running when you have it on recirculate
I just bought an aftermarket set for $150. Seems a lot easier to put the sensors in and not worry about it for the next 5-7 years than go through all the trouble trying to get rid of it. My local dealer can't get any programs from GM for add ons that aren't "factory accessories" through GM...