My grandmother has this 01 Silverado 1500 that she may consider selling soon. I’m not too familiar with the GMT800, so maybe you’ve got some helpful input!
It’s an 01, 1500, extended cab, short bed, 4x2. For reasons I cannot explain, I forgot to pop the hood and inspect it but I think it’s got the 5.3 v8 (?) My uncle bought it new, he passed away shortly after and left it to my grandmother. She hasn’t driven it much, and her health may be causing her to reconsider driving.