Take that wire back off. It's not a ground. If you crank the engine with it attached you'll burn the wire. It will be a dead short while cranking.

That might be a 12 volt starter. They're the only ones that had the small terminal on the side to bypass a resistor used only with 12 volt ignition systems during cranking. Take the starter off and measure the shaft diameter like I suggested.

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Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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