On a point-type ignition system, anything that can flow up to 5 amps comfortably will work. That would include 18 gauge, but that would be stretching things a bit. Voltage drop from the ignition switch to the coil would be a concern, especially in a 6 volt system.
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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