I've never done the job but from what I understand the starter and the wiring will be ok with the higher voltage. So all you need to do is change the bulbs, adapt an alternator and change the coil. Most alternators are negative ground so you will need to change the battery connections as I believe the M is positive ground. Also the connections on the coil. On a positive ground system the points need to be hooked up to the negative terminal of the coil. You might need to replace the resistor for the coil but I'm not sure on that. If you buy a coil for a ~ 60's Chevy with an internal resistor then you can just wire the + side of the coil direct to 12 volts.