well i have a 85 suburban that is all stock except for the 3/5 drop and being totally shaved.. i realized many problems when lowering this vehicle that suburban and truck frames werent as close as i had thought.. my dad has just purchased a 87 2wd crew cab dually with a 4speed manual and a 454..he called me while i was in class, left a message and at the end he said " its clean and i wana slam it to the ground".. we are going to put a flip kit on the rear and springs and spindles on the front..what heigths would you recomend..i want a 5/7 drop for it, but we might still use it to haul a trailer or something every once in a whiel..would a 4/6 be better for this..and for the rear, we will get helper bags..any advice..thanks..ill post pictures of it when i get home..

and also..does anyone know how well a 5speed out of the obs trucks will, if not directly bolt into this dually? i wouldnt mind getting a little bit better gas mileage..thanks