, quick question. As many of us that started out with the LT, I want to upgrade to the stock ss 20s as well and noticed that's what you started with. You still have 20s from what I see. Did you come across any problems with the speedometer or any problems in general? a GM dealership's service center is giving me a hard time with trying to put some stock SS 20s on my 1LT that came stock with the 18s like your's did originally.