If it's an original 12 volt application, there should be a small connector for the resistor bypass wire, and a 12 or 14 ga. wire attached to it going to the coil (+) terminal downstream of the ballast resistor. The 10 Ga. wire should go from the battery cable terminal to one side of the ammeter.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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