16 gauge ought to be plenty. It's a fairly low-current circuit. There's a nickel/chrome heater coil wound into the choke housing that provides enough heat to help the choke release itself quickly.

The first electric-heated chokes were used by Ford in the 1980's, and they ran a 16 gauge wire from the alternator stator winding to heat the choke housing. That one only produced power with the engine running, which accomplished the same result as using an oil pressure switch. It would be difficult to tap off a GM alternator that way, and just about impossible to do that with a DC generator.

Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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