Hey Pat .....In the case of 12v/NEG GROUND, well that's easy, peazy TOO! Of course, NEG BATT to chassis GND (instead of POS BATT to chassis GND). Hot wire from ignition switch now goes to POS + coil. NEG COIL - now goes to distributor. ALL light bulbs need to be changed to 12v bulbs. Old Ford SOLENOIDS regularly operate on 12v for years (or until they don't any more). 6v STARTERS run just fine on 12v, until they don't any more....STARTERS are not polarity sensitive. SOME radios are polarity sensitive. Gauges need to be converted to operate on 6v. Coop
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