1975 duster 360 exhaust question

Question- how many variations are there for A-Body manifolds?
That is a great question I can not answer off of the top of my head. I’m not even sure I have a book that could, but, I’d bet the interchange book would carry that information. It covers mostly the muscle gears of all engines, trans, rears, brakes, etc... parts of the car with casting numbers and what is and what is not swapable between years makes and models.

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