Since you have a Z71, you could do what I just did. I put on BOSS 309 series 20's with Nitto Mud Grapplers. I have the color matched fender flares on my truck. I'm going to get another set for daily driver, but I have a show vehicle and need a good aggressive look for on the floor. I should be getting a pic of my truck in a day or two and will post it. Instead of trying to pull the block, you could get bigger tires and use your torsion bar to lift up the front to fit bigger tires and give a flat ride. My torsion bars are up about 2" on each side and the truck looks really nice. I've gotten a lot of complements on it in the 6 days the rims and tires have been on the vehicle.
2002 Chevy Silverado Z71
Alpine DVA-7996, PXA-H700, KCA-420i
Audison LRx 1x400 and 3 1x250
Focal Beryllium Tweeters and 8" Sub, Focal Utopia 7" Midrange, 2x Focal Access 40A 16" Sub
K&N Air Filter, Flowmaster Exhaust, Hypertech Programmer III, 20" Boss 309 on Nitto Mud Grappler 33x12.50R20