not sure about 3drs, but 2wd saphs have differant front chassis legs to the 4x4,
on the 4x4 the legs have a little arch to clear the shafts on full suspension travel,
the 2wd shells dont have this(i've heard some do but not all),
i've had probs with 2wd shells i've converted to 4x4,
could poss be this, worth checking for any signs of runbing above the front shafts