Monte3 and EricD both bored out chevy rally wheels with no problems. Tay did it on chevy aluminum wheels by hand with no problems, the montero lugs will put the wheel where it needs to be but i say get 15x10's you'll be fine. A lot of us are running 10's down here and we usually air down to 8-15 psi for rock crawling and i've seen 2 popped beads ever one on PAJ_ERO's 35x12.5' on 10's and one on 31x10.5's on 7.5's. I run 35x13.5's on 10's, 12's are good for 14.5+ width tires which you can get in mickey t's, swampers, pit bull and toyo to name a few.

1999 Montero SAS'd on Kings and stuff

1998 Montero trying to get a V8 Swapped