My stupid, there are 3 smaller battery cables bolted together right at the positive terminal of the chassis battery. After looking at the diagram Tfryman sent in an earlier post, I realized the field on the alternator wasn't being energized, and hence no charging by the alternator.
I looked again at the battery connections and one had fallen out of sight and I missed reconnecting it.
Bolted it back on with the others and now alternator charges again and dash light is gone.
Thanks so much Tfryman, you gave me the clue I needed.