I think the yj's are 2.5 inch wide(have to go look now) and they just use the stock size perch, you can run the yj's in the rear and then put you rears up front with a r.r.(r.u.f.) kit or make your own but the yj's might be about two inches taller in the rear than the front if you have a winch, the shocks make for the ruff ride, check out sky's kit or trail toughs, t.t. sells new yj's cheap also,I run yj six packs front and rear.