-- You may want to switch out #1, the voltage regulator, to a modern solid state type.The old mechanical type with points can do what you have stated.(It did on my 67) Try a Wells VR706 from a parts house such as Auto Zone or Advanced . --
-- Installed a new VR706 - No change, -- Hate to spend the bucks - BUT - I'm headed to repair shop/mechanic. -- Thanks to all. -- I'll report on the results.