Sadly, the recent server crash lost many posts of interesting and (what I thought) somewhat useful information. The II trivia thread in particular comes to mind, on a rainy day such as the one I'm experiencing right now. Anyway, I recall some mention and discussion of II's that came with dual exhaust systems vs those that came with singles. A close look at factory shop manuals for '75/76 explains this is greater detail, and hopefiully will provide additional clarification for anyone (myself included) that had thoughts on it before.
Charts show that both V6 and V8 models were available with either system under certain conditions and at different times. Early 1975 V6 and V8 cars had duals, but late 75's and all 76's were singles... with duals only being available in Canada. 49 state late '75 models with singles had only one converter, while Calif models got two. All 1975 (V8) dual models had no converters, while V6's had two....and all '76 V6 and V8 models in both single and dual configurations had two converters, with the exception of the dual exhaust Canadian cars, which had none. Lastly, all dual system cars (with or without converters) used dual resonators, but with a single muffler. It's my guess that those dual exhaust cars (both V6 & V8) got the muffler that had two exhaust tips.
Charts show that both V6 and V8 models were available with either system under certain conditions and at different times. Early 1975 V6 and V8 cars had duals, but late 75's and all 76's were singles... with duals only being available in Canada. 49 state late '75 models with singles had only one converter, while Calif models got two. All 1975 (V8) dual models had no converters, while V6's had two....and all '76 V6 and V8 models in both single and dual configurations had two converters, with the exception of the dual exhaust Canadian cars, which had none. Lastly, all dual system cars (with or without converters) used dual resonators, but with a single muffler. It's my guess that those dual exhaust cars (both V6 & V8) got the muffler that had two exhaust tips.