1962 -1967 = 3 synchro transmission. Inertia starter, a.k.a. the "Lollipop Starter". External, or "remote" solenoid. One single power wire going to original starter. 1968 - 1980 = 4 synchro transmission. Pinion gear has shroud covering it. Internal solenoid. 2 or more wires going to original starter. (See picture for visual differences)
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