I'm working on an old Farmall bn. I took the old non working generator and put a 10si gm 3 wire alternator in it's place. I'm running new wires to connect it up. The main charging lug I ran to the pos. Wire on the starter. The sense wire I just looked back to the charging stud. The Exciter wire is what my question is. This tractor has a magneto so no key switch or positive wires on the tractor. Just a wire from magneto to a switch that runs to ground to shut the tractor off. Can I just run the sense wire right to the battery or do I need a switch inline that I would have to switch every time I start the tractor to turn on the alternator.