I can understand it on a 100% original car too. But then I would probably cheat and just have a non-functioning external regulator bolted in place just for looks. [/quote]

I'm calling BS on this. You're prices are way out of line. First, you don't swap out an entire charging system just because it needs fresh bearings or brushes. Maybe your GM dealer is bending you over frontwards insead of him bending over backwards to help out. A quick look on Rock Auto shows a Remy reman alternator costs $36.98 if you keep the core.

With an extra hour spent, since we won't count R&R in the comparision between replacement vs original, you can put fresh brushes and/or fresh bearings in the original alternator. Rock Auto shows their most expensive brush set at $6.95 and the bearings at $4.52 or $10.36, depending which end. They have cheaper selections as well. The rectifier assembly cost $7.65 for their most expensive part. The rectifier is readily checked with a $4 Harbor Freight meter looking for shorts or leakage. There's not much else to go wrong inside an alternator unless the windings burned down and shorted. That's pretty rare, in which case you could buy the Remy complete alternator unit.

Rock Auto offers quite a few external voltage regulators with prices ranging from $10 bucks to $60 bucks. I would pay up for Delco unit.



I picked up a later model new-in-box "NOS" Delco regulator on eBay for $50 w/$8 shipping so I would have a spare that had Delco embossed in the cover.

I think there is great value in maintaining the car to it's original configuration, especially when there is no performance gained or problem solved with modifications. This is one such instance. The original Delco regulator from my 68 bird with over 100K on the clock looks like new inside. I will install new brushes and new bearings in the original alternator as preventive maintenance measures to put things back restored as GM shipped the car in 1968. The original bearings are still servicable with higher milage unless they are making noise, but in my experience, brushes are on borrowed time after 75K miles.

The original charging system is adequate for the Firebird's configuration as the car was shipped by GM. You don't need hundred plus amp capacity unless you add accessories that pose high loads, such as electric cooling fans or electric water pumps. The original wiring doesn't support those high currents without further upgrades.

I think the myth of one wire or use of later model "internally regulated" alternators stems from the inability of shade tree mechanics to diagnose eletrical failures down to the component level. That's pretty much what Terry said too, when he said a professional mechanic fixes what is broken. Otherwise you're playing junior engineer. A one wire alternator is a "modular solution" pretty much likely to repair a charging system that has an undiagnosed problem. But it also doesn't provide any dash lamp warning that the alternator has failed. It's like replacing a complete flashlight with new because you don't know if the batteries, the bulb or the switch are bad.

You could actually go backwards on charging system reliability with the "upgrade", because newer solid state alternators are accomodated by better grounding design in the wiring harness design. You would have to rewire the harness to achive the same results. Solid state regulators (like solid state ignitors) are subject to transient voltage damage that was never contemplated in the electrical design for the Firebird in 1968. Solid state ignitors run longer without any adjustement until they burn down without any notice. But they don't work any better than properly adjusted points. Points and condenser won't strand you dead-right-there like a voltage transient will with an ignitor.

An original voltage regulator will fail when the contacts are burnt up. An alternator will fail when the brushes are worn out to nubs regardless of the regulator internal or external design, and sometimes without much warning. But the original alternator won't fail from voltage transients caused by jump starting or loose wiring like a solid state regulator can.