I have a two pin alt on my 52 1/2 ton. I also have a 12 volt regulator. No one wire here. It takes a single rev up to about 1000 rpm to get it charging. Works fine and has no issues. I hit that rpm range at the first shift point from my driveway and after that no problems. I only use one pin out of the two, battery. It might be an internal regulator? It might not. It works so I have not messed with it. Will yours self excite at higher RPM? If not you might have a defective BOOB(Bad Out Of Box) regulator. Load switch like your headlight switch won't have any effect on the alternator, But might cause some issues if not fused.
