[Oldsguy]

You should re-wire your primary circuit. New cable from the battery to the alternator via the relay C.J. metioned. New cable from the relay to the starter. New wiring wherever you find a splice or "mickey mouse" setup. That is why you got the overheated wiring problem and smoke, poor connections caused excessive resistance in the circuit which cause the heat. Bad, bad, bad. If you don't fix it you are asking for a fire. Oh, and a new battery too.