adding a charging fault light

On the older Delcos, the lamp circuit is the "exciter." Originally it was lamp in parallel with a resistor, so if the bulb failed, it would still excite. Frankly I'm surprised that an LED would excite "all" Delcos. Might be a "one wire" regulator.

Many guys used to mistake using the older Delcos in a swap, leave out the lamp, and wire the no1 connector direct to the key. That might work once, twice, or 507 times, but some time or other, it will take out the diode trio. You must have a diode or resistor or lamp in the no1 lead to protect it.

Some of the later model Furies? and other sleds had a warning lamp for the charging system. I will have to look them up. Forget what was involved, there

EDIT cannot find the bloody thing. First year I see mention is 79, was evidently a solid state voltage indicator (light came on with low voltage) but the wiring diagrams have it pretty well hidden LOL