I ran 31x10.5" Goodyear MT/R's on stock rims, 1" spacers on the rear, no spacers on the front, a 2" BL, 1.5" T-Bar crank, and 1-1/2" lift rear shackles with very good results. The front and rear track were exaxtly the same with 1" spacers on the rear, and I only had a little bit of frame rub when the front tires were turned all the way in either direction. There was no rub with the rear tires even when fully flexed. I got rid of most of the front tire frame rub by welding a little material to the factory wheel stops on the lower control arms. The only other thing I did to clear the 31's was cut off the sharp corner on the lowest part of the front wheel opening toward the rear. I did this without cutting into the inner fenderwell or beating anything up with a BFH. I could take that truck anywhere off road without any problems! I think the perfect backspace for 15x8 rims on these trucks would be anywhere from 5" to 5.5". I had Black Rock make some 15x8 rims with 5" of backspace for my 05 ZR2 Blazer. They are all black and only cost me $110 each. These would have fit real nice on a CC!
2005 ZR2 Blazer / Mods- Spectre CAI, Descreened MAF, Shaved Throttle Blade, 31" Goodyear Kevlar MT/R's, Black Rock Rims, MSD Street Fire CDI & Super Conductor Wires, Accel Cap, Rotor & Coil, Flowmaster 30 Series, Gibson Tailpipe, ES Bushings, Goodridge Brake Lines, Power Slot Rotors - 1996 Impala SS / Mods- Too Many To List - 1988 S10 Blazer / Mods- Too Many To List - 2001 S10 Crew Cab 4x4 / Mods- Too Many To List *Wrecked 12/06*