Need assistance/info --exhaust

The engines in the 63 & 72 surely matter. Can you tell us? I am guessing a slant six since that was the only option in 1963. Later A-bodies were longer, so might have to cut out a straight section, but that isn't hard. Later models were also slightly wider, but that may not matter. Where it passes under the scallop on the driver's side of the transmission support is the most critical location. Does it clear the torsion bar?