From what i can tell a -12 offset on a 9" wheel is the equvalent of 4.5" of backspacing. I run 285/70r17's (33x11.5) on a 17x8 wheel with 4.5" of backspacing on my 2 door x w/ no lift and my tires stick out at least an inch to inch and a half. I don't rub at all on the street but rub offroad. So with 33x12.5's combimned with those wheels you be sticking out about 2.5 inches which by the sounds of it is what you are looking for. You may rub a bit but hopefully some other people will chime in. Hope this helps.
2008 X 2-door, 35" Duratacs, Clayton Long-arm, geared and locked
2012 Rubi 2-door, 37" Nittos, Method Beadlocks, JKS Suspension, JCR everything