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The ammeter is wired wrong or the battery is charged backwards or connected backwards.
It is possible to charge a battery backward, making the positive (larger) post negative, and the negative (smaller) post positive. This can happen in several ways, one being putting battery charger leads on a very dead battery on backward. If your battery is charged backward, it might be possible to save it by allowing it to run down overnight with a light load, such as parking lights. When it is fully discharged, older style battery chargers can usually recharge the battery with correct polarity. Many modern chargers will not.
Assume nothing, check everything.

Oh silly me….I wasn’t ever thinking about the ammeter being wired backwards. That is almost certainly what is going on.

I know the battery is wired correctly and is good..(new optima battery) and I’ve measured the voltage and get the correct voltage and polarity. Battery is good.

Now, back in 2004 the wiring harness was replaced. Almost certainly, the ammeter got connected backwards. If so, it won’t hurt anything. I’ll flip it around when I get a chance.

Thank you all for the help! This group is awesome!!

I believe it's normal for the ammeter needle to bounce or twitch slightly at idle. It may be due to the voltage regulator cycling. Generator output is very low at idle and may even fall below 0 a low idle.

The rate of charge will vary with the battery's state of charge and engine speed and accessory load. A discharge condition may be normal at engine idle with lights and accessories on.

Thanks again for all the help.

I think that last week when I was driving the battery was discharging the all the time.

So, other than the meter being wired backwards, I think everything is working correctly now since I polarized the generator tonight.

Everything had been completely disconnected when the wiring was all replaced back in 2004 and the car was never started again after that.

I’ll find out this weekend when I get it out for enough of a drive to get things warmed up. Then, I’ll get that 20 year old oil changed.

The gauge being wired backwards won't discharge the battery. It is only an indicator and will read backwards but the battery should still be charging so I expect that's only part of the problem.

I think the original problem was the generator not being polarized after the re-wiring back in 2004. It was never re-polarized after that and the car never ran again until a week ago.

Based on what I’m seeing now, the only issue is the meter reading backwards which isn’t really a problem..

I'd charge the battery fully before any further driving.
After charging the battery and driving several miles and observing some level of charge with the ammeter indicating correctly, you should be able to stop the car for 5 minutes or so and then be able to re start it with no issues.
If it still acts like the battery is low, you could have an ignition timing issue. (This assumes the starter is good and the battery and generator are working correctly and that all connections are good)
If the initial timing is too far advanced, a car will often start easily when cold , but fire against the starter when warmed up. This situation can mimic a battery or starter issue, when the actual problem is the timing.

Thanks for the help. I’ll definitely see how it does. The battery is fully charged. I did charge it after the last drive.

As I mentioned, I think the issue was the generator not being polarized. We shall see!

Okay…good news.

I got the car out today.

After determining that the ammeter is just wired backwards and polarizing the generator, I got it for a short drive. I had checked the battery voltage last night and it was just over 6.4V. When I got back from the short drive, it was at 6.5V…

I then took it out for about a 40 mile drive since the weather here was gorgeous today. All good. When I got back, the battery voltage was still good.

Thanks again for all the help!