- Surprised you are back on the Alt/Reg again. (1) - Thought you had both tested and confirmed.
I have not read all your posts, but to re-cap.
(2) - Flickering lights at idle and jumpy amp gauge
(3) - Tightened amp meter feeder wires and fixed. (4) - Now you have the issue at cruise speed? (5) - Do you have electrical loads higher than anticipated from a factory car? (6) - Have you done the MAD modification?
(7) - Does the issue only happen when the lights are on?
(8) - Are the grounds from engine to firewall connected ?
(9) - From neg. batty terminal to rad support ?
(10) - Have the main feed wires in and out of the bulkhead connector been checked and cleaned? (11) - As well has the ignition feed to ballast/regulator through the bulkhead been checked and cleaned? --