I ran 33x12.5s on the 15x7 alloys on my 88 p/u with no lift and no rubbing once i took the sway bar out and still had room when flexing, although i think the 3rd gen trucks have a little less room.
My 2 cents.

88' Xtra cab, 22RE, 5 spd, alumi flat deck, 3" BL, 35" muds...awaiting SAS.

'02 Ram, 4.7, REV 'Shooter' wheels wrapped with M.T. Baja claws.