help with the fusible link wire smoking under the dash as i drive

ok, here is where i am at. i took the alt off of my 70 /6 duster that has electronic ignition. my 70 340 has points. would the alts be the same? cause the /6 car had a dual field on back of alt, and my 70 alt had one field wire and one grnd wire on back of alt. when i put the 340 alt in my /6, it immediatly fried one of my field wires. so i took the fried wire off, and just left the one field wire on it, and it starts and runs fine.

now i took the /6 alt and put it on my 340. and now the wire to the ammeter in the dash is not getting hot anymore. but i want to make sure it is correct
i no longer smell wire burning

would a 70 duster have one field wire and one ground wire? or are they both field wires? if it is supposed to be two field wires, then they put the wrong alt on the car at one time