2000 Tahoe - Need help and/or advice

Hi. I'm new to this group and I have a question. I have a 2000 Tahoe LS with 5.3 V8. About 2 weeks ago, my security light came on (steady) in my message center. After reading the book, I found out that my PassLock Theft Deterrent System was not working, but I could still drive my truck. After numerous inquiries, I have figured out that I am probably going to have to replace the ignition switch and cylinder lock. My question is: How long should it take a professsional to install this? How difficult is it to replace? I'm trying to get an idea about costs so when I go to a mechanic, I will already have an estimate about charges. I have already estimated about $120 or so in parts and just want an idea about labor. I have already have to spend $1217.48 on a new compressor, tensionor, etc. back in June because my air quit working and the compressor was making an awful noise whenever it engaged or I accelerated. Apparently the problem was so "rare" that GM didn't have a clue on what the problem was and recommended that the entire compressor system (including hose assembly - which we didn't replace - an additional $500.00) be replaced. I really love my truck and am hoping that this is just a minor inconvenience.

PS, we have tried resetting the computer, cleaning the ignition switch itself, and cussing and ranting and raving, all to no avail. If anyone has any suggestions, options, advice, recommendations or ideas, I would greatly appreciate it.

Thank you,

I guess no one has any ideas or recommendations. Thanks for reading my post anyway.

i have a 99 tahoe doing the same thing. The light comes on and the truck won't start.I am not sure of the price,but i believe there is a way to bypass the passlock system.Check with your dealership for more info. And on the compressor deal, my compressor squeils very bad when i turn my air on too.I'm sorry to tell you this, but you got taken advantage of. The problem is the pulley assembly.The bearings wear out and cause it to squeak.It is a pain but you can just change the pulley instead of replacing the compressor. Alot cheaper,but alot more work so GM replaces the whole thing.Sorry!