Everything seems to work except the alternator isn’t charging the battery now. Tom and Ray suggested to take the alternator to a parts dealer who’ll test the alternator in their test fixture.
If it tests bad, the problem is most likely one or more of the alternator diodes has burned out. This problem can easily be repaired. A fix-it-yourself-handiman type could do it themselves. But the easiest way is to take his alternator to a local auto-electrical shop for fixing. Either ask a local mechanic where the closest shop is, or look in the yellow pages.