The Mk3 inlet (and exhaust) is the same as the standard truck one,and shouldnt be hard to find locally.....(may need to be C line for a 281 motor.?).....the exhaust has a rib cast into the lower edge,that the Cline didnt have,but otherwise it all fits......The rib doesnt stop cracking ,but the two piece of the Mk 4 does positively eliminate cracking.
