. Back in the early '60s My brother-in law came and got me the help his brother get his '28-'29 (did know which yr.) started. Well, When I got there they had all the wires to the ign. all messed up. They had taken the ign. coil off a '58 Harley motor cycle and had it wired in. The first thing that I did was tied the ign. coil to the distributor and then coil to the ign. switch. Got spark at points and plug. every thing ready I hit the starter. The thing started right up, idealed just fine, Here is the funny part, My brother in law told me to turn it off, I turned the ign. switch off and the engine keep on running 
I said I have the switch off. My brother in-law said I'll get it, so he reached over and pull the coil wire out of the distributor A blue spark followed his hand up over and back down below the gas tank, I saw about 12" of spark above the tank go up and circle back down behind the tank . I have never seen a spark that that hot on an A model again. It might be that they had a motor cycle coil on it and he cirrent was coming straight from the generator still to this day I can see that blue spark following his hand
Shelby, SacramentoThe brother gave me the '58-60 series harley for getting his A model running. I bought a new ign. coil got it running
45 mph was its top speed Traded it for a '49 olds. coupe