275/60/20 seem to be the most trouble free size to run 33's. I haven't decided if I'm going to stick with 20" or go to 18". If I stick with 20", that's the size I'm going to get (no lift or level). Might try to get a set of Rebel 1" suspension take offs (or BTS). I like that height.
Other sizes I've noted. Some may need to trim or take a heat gun to the wheel liners.
295/55/20 = 32.8” x 11.6 wide
275/65/20 = 34” x 10.8 wide
305/55/20 - 33.2" - Supposedly fit on stock wheels, stock height, no rubbing.
Any larger and you either need a level, lift, or a Sawzall.