I'd say you may have some trouble with the front. I'm at 18x8 and I scrub when I turn to the lock. An extra inch in height and a half inch in width might be problematic. As for the rear that might be doable. A 20x10 ET40 would have about 10mm more backspacing than my wheels. But it would stick out a little more than mine, about 16mm. A good suspension shop could make it work.(I think)