First of all, you DO need to change the oil. I didn't take any chances on my '54 235, even though nothing drained into the oil pan. Secondly, the starter will be fine on 12v, and should already be it if it is off of a '55 first or later engine. If it is still 6 volts it will still survive anyway, they last a long time on 12v. What about points and condensers? Plug wires, all that? They should probably be replaced.
