Thanks!
I've owned GM trucks for years, first time doing custom wheels. I got motivated to do it when the factory 20s got scratched up when I got stuck doing normal truck stuff. I'm much happier with the 17 inchers. It's just my experience, and people use their trucks differently, but for me the fact that the factory SLT 20" wheels are flush with the tire sidewalls makes it too easy to damage them.
Each to his/her own!
This forum was my main source of information on wheels/tires/offsets/rubbing/leveling kits when figuring out what I wanted. Worked out great for me. Appreciate everyone's information and willingness to help. Good stuff!