Ordered a new alternator online for a 4430, Delco style. Old one is a reman, I assume I got it at Deere. New one has three spades to connect, one post marked B. I assume the two spade connector from tractor just goes on the two beside each other on the new alt. The two wires with eyelets goes on the B stud. So what is the third spade for ? Different wire harness ?