[Dave at Pelican Parts]

The output flanges on the 1.7/1.8 heat exchangers are higher up off the ground (closer to the trunk floor) than those of the 2.0 motor. The 1.7/1.8 muffler has its inlets in the middle of the muffler, the 2.0 has its at the bottom of the muffler. The muffler hanger of the 2.0 also comes down lower, as it bolts to the output flanges of the heat exchangers.

Note that this all applies only to the 70-74 cars; the 75-76 cars have an exhaust that is completely different from the early stuff. There is no difference between the 75+ 1.8 and 2.0 exhausts, though.

--DD