I was running 1.5 inch spacers with the Trailhawk stock rims (17X6.5, +40mm offset) with BFG KO2 225/65R17 and updated to the Method Racing MR701 (17X7.5 +30mm offset) with BFG KO2 245/65R17 and 1.5 inch spacers.
I can't imagine going any larger than a 245/65R17...
I'm using a 4" lift (AVID 2.5″ Renegade Lift System and ATP's Renegade/Compass 2.0 Coil Set), 1.5" spacers, pinch weld and fender liner modification and still have tire touch on the rear of the front tires. Nothing major, but I'm still going to have to cut more pinch weld out of it.
BUT, I do like the way thigs turned out.
I can't imagine going any larger than a 245/65R17...
I'm using a 4" lift (AVID 2.5″ Renegade Lift System and ATP's Renegade/Compass 2.0 Coil Set), 1.5" spacers, pinch weld and fender liner modification and still have tire touch on the rear of the front tires. Nothing major, but I'm still going to have to cut more pinch weld out of it.

BUT, I do like the way thigs turned out.