Now that I have a little coffee in me, check your battery. 12 volt or 6volt? That may be the easiest way to tell. If it's 12 your coil will be 12 also, and there will be a ballest resistor, usually found on the firewall between the ignition switch and the coil. It probably will look like a ceramic block about 1 to 1 1/2 inches long. Follow the lead from the coil that goes back to the cab.
Man, coffee is good!
Have fun. Let us know what you find.
