The coil got hot because you probably don't have a ballast resistor. Even a 12V coil is only made to handle about 8-10V. As for the wiring, it should be the same(do you have plastic or cloth?) If you are running the original starter and it was 6 volts don't crank it forever or you'll burn it up/ I converted my old ford 860 tractor to 12V and the 6 volt starter works fine..spins it fast. Anyway check for a ballast resistor or with a multimeter to make sure you only have 8V or so at the coil...that's why it worked with the 6V battery. Hope this helps. Later
Dave
