Hey everyone just finished lifting my 87 pickup and now its time for wheels. I've got a 2in body lift and 2in suspension lift. I'm wanting to run 33/12.5/15 or maybe 35s still on a 15 rim if y'all think they'll fit. So my question is for the tire sizes stated what back spacing should I be looking at? I'm primarily wanting the pro comp rock crawlers in a 15x8 size.