Thanks for the responses but I am still confounded!!

Well I may not have explained things clearly and I also had some typos

The bus stopped charging for no reason and the generator light remained on.

I reverse jump started the bus and it was Ok but I blew my radio, luckily no
alternator in'70

I bought a generator & regulator from the junkyard, VW used parts in San
Jose, $40 gen $10 reg, both returnable if not needed. To check the generator
at the junkyard he wired it up to a battery and it motored, I did the same to
mine and it  motored fine.

I replaced the regulator with this new looking shiny one that had german
instructions on the side and the same connections.

Now the regulator puzzle, underneath the original regulator is a puzzle. It
is a black box 2"*1"*3/8", it had the wire from the generator that went to
the warning light (#61) going into it and a terminal that was connected to
the warning light. What could it do and do I need it. I cannot see any
reference to it in the Bentley manual or the Muir Bible. Well I just guess
that I will have to charge over night and run. I have to get it fixed if we
are to go camping at the end of October.