Has anyone put a chin spoiler from an 05 sierra on to an 03 or 04? If so, how and what did u do ta make it fit properly. Second, how hard is to change out the t-stat on these trucks? Thanks for the input.

 

I'm not sure about Sierras, but I looked into this for my Silverado and it requires not only the chin spolier, but the entire lower plastic piece from a 05 truck as well. Yours might be similar. Try snooping around the lot at a local dealer.