I have 32X12.50 on my stock 92 Nite Bronc on 8" alloys and have no trouble whatsover.
I also run 35" tires on my 85 bronco, but had to cut some sheet metal to do it. I followed the body line. It still rubs when getting crazy, but not too bad. My 33X14.0 boggers also rubbed before I cut the body, although I've seen 33X12.50 BFG's on stock Broncos without trouble.
Watch you wheel offset!