I have both a 12 volt Dodge and a 6 Volt Dodge. Rules are the same for both, keep your earths clean and tight! Fix connections to earth and starter with toothed anti shake washers. Current flows on the surface of a conductor, and as Volts X Amps = Watts a 6 volt requiers double the amps, so ideally double the surface area of the condutor. Both mine have Frank Jolley's electronic igntion units fitted, that has improved them more than anything.