The 12SI Delco alternator is a very good up-grade for many makes and models. We have all seen them used as an up-grade on Chevy and other GM cars. Here's one that has performed very well on a FORD, for many years and lots of miles. At the time of this writing it still serves as a daily driver. Often this alternator has had to work hard, and sometimes for long days. There are four electric radiator fans (all come ON at once), another fan on a transmission oil cooler (foreground), a powerful air conditioning system, a small sound system, electronic ignition, Halogen Headlights on relays, and there are two batteries that must be maintained. It's a stock, DELCO, THREE-WIRE alternator, and was wired using M.A.D.'s part #ALT-1 kit. The system also operates the factory "GEN" warning light at the dash at this '64 FORD.
The FORD (shown in previous photo) is a '64, which came with a generator, not an alternator. It's a nice touch to make use of the original warning light at the dash, when using a stock dash system. And this GEN light works perfectly with the THREE-WIRE 12SI, wired using M.A.D.'s part # ALT-1 alternator wiring kit. (Shown with Ignition Switch ON, engine stopped.) The THREE-WIRE system will also support the factory "ALT Warning Light" when converting from the externally regulated alternator systems.