Well if im not mistaking a 3" BL will clear 31's and some kind of coil spacer in the front with some shackles in the rear should do the trick with a little fender trimming. thats the cheapest way prob less than $200 for the works
my brother has a 4" rough country lift attached to a bronco II just sitting in the yard. no motor or tranny in it. if your interested i could ask him what he want for the whole thing