Gary,
Dirty regulator points will stop the generator charging. As you have found, the regulator points tend to get a build up of corrosion which is an insulator. The cut-out points don't seem to get this problem but they are silver and the regulator points are tungsten.
Try checking the voltage across the battery with the engine running. If you get 7.2v or so and it doesn't drop below say 6.5V with the lights on, I would leave it be.
The regulator is fairly easy to adjust, get a set of service sheets for details.
With a fully charged battery, you shouldn't see a high charge on the ammeter. If the ammeter is showing slightly positive with the lights on and some revving, it seems OK.
Trev.