Bill, I didn't expect that the alternator was electronically faulty but recently, as in the past week, I heard the bearings howling a little. I figured that I would put bearings in it again while the car was down, I had no idea how noisy they were until I removed it and spun it. The headlights seemed to be fine and I just figured that I wasn't used to driving the Bonneville, they were surely dimmer than my truck.

The gauges were kind of whacky since the engine was replaced but really not a problem. I'm guessing that I will see a marked difference once replaced.

The celebration may be premature.... I installed the replacement alternator and put the battery on charge. I started the car and see 38 psi of oil pressure knowing that I have 50! At idle it drops to a little more then 20 and this is before it warmed up. The volt meter still looks goofy bouncing around like always. At this point I have little confidence that it is fixed but I still need to test drive it. My only hope is that it was back to the stage that it was before it dropped. Even if the gauges read low like thay have for the last few years, thats OK, as long as they don't drop to 5 psi and set off the dinger.

Update: The replacement alternator made no difference at all.... I removed the used alternator and took it to a shop and had it tested, it is fine. I installed a new Optima battery on loan from a friend.. no difference.

At this point I'm thinking gauge cluster or computer. I have been unable to get an answer anywhere as to how the oil pressure and volt meter get their data. Does it read it directly of does it go to the computer and the computer sends it to the dash? Ths other odd thing today is that I had a "check gauges" light on solid this morning. I accidently left the key on for 4 hours at a friends house today and killed the battery, once jumped and started the light is out

Update: Replaced teh entire cluster and it made no difference! The replacement dash exibits the same symptoms as the original.

Anyone know anything about the BCM or the computer as it relates to the gauges?

Well, that didn't fix it! I have since redone the grounds again and replaced the gauge cluster, I then found 2 grounds down behind the front kick panels in addition to the buss grounds. None of these things fixed my problem....