My guess ...
33x12.50 with the lift your talking about would take 2.5" BS wheels. And you will be trimming. With that, I suspect you wouldn't rub.
I've got 2"BL, 1.75" spacer lift, fender trim job, 3.75" BS rims, and 31's have zero rub. I'm very close to being able to fit 33's, so your plans should do you fine.