Our popular "SI" Delco 3 wire Alternator is just the ticket for your 12V conversion. If you're wiring your Tractor yourself and need an Alternator for the charging chores, here's the perfect candidate. At 65 amps, this baby makes more than enough power to take care of most Tractors large or small. And, equipped with our CNC machined 5/8" pulley makes this combo perfect for the job!! Outright. No core.  Wide belt 5/8" pulley included.