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Hey. Doesn't bother me. Bumps it back to the top where more people may have input. Ha

Dennis, you're reminding me why I don't miss California.

OK, nothing special about the 78 gauge. I would have been surprised if there was. So if that resistor DOES exist, it's not in the gauge. Thanks for checking. If it exists, it's probably a plug-in like the tach resistor, but I don't have any 78 harness stuff to to poke around with either. About the brake warning lamp stuff... In 78, the brake warning lamp check relay is wired in parallel with the charge lamp and hence, it will supply additional current into the alternator rotor windings at bootstrap. So in 78 at least, it might not be that a blown bulb would render the charging system incapacitated. Depends on the resistance of the relay coil. I don't know the resistances of either the charge lamp filament or the brake check relay coil, but it would be interesting data. In my case, I've got a 77 with a charging system rewired like a 78, including the brake check relay. However, prior to my alternator upgrade changes, my brake check relay had already been disconnected because it wasn't working properly. So in my case, there's a chance that if I were to wire in a 78 style brake check relay the additional current draw through the relay's coil would be enough to get me up over the bootstrap hump. So yes, your charging system (and mine and probably everyone else who has done the internally regulated alternator mod) is relying on that single corroded bulb. But in theory at least, you would know that you had a problem because the charge lamp would not light up when you turned the key to ON before you cranked it. You're SUPPOSED to scan the entire dash for anomalies before your start the engine. I know nobody does this, but you're supposed to verify that the brake and charge warning lamps light up properly. It's a bulb check safety procedure. Just like the bulb check mode on a new vehicle. Every time you get into the vehicle. Make sure the bulbs work - Check Engine, SRS, BRAKE, TEMP. Yeah, I don't do it either. In 76, the brake check relay was driven by the alternator as well, but it was done a little differently. In 76 and 77, they used a set of normally closed contacts and energize the coil when the alternator is working properly. So if the alternator stops working and the N connection goes dead, the brake relay coil de-energizes and lights the BRAKE warning bulb. In contrast... In 78 they use a set of normally open contacts and de-energize the coil when the alternator is working properly. So if the alternator stops working and the L connection goes dead, the brake relay coil energizes and lights the BRAKE bulb. That's why you needed to find a different place to connect your 76 brake relay coil. The sense of determining proper operation changed between 77 and 78. They both need a "high" to shut off, but the 78 won't "supply current", only "not draw current".