I note he has a one wire alternator which would render the dash mounted alternator light non-functioning (NOTE: All the external voltage regulator wiring should be removed or disconnected) so any bleed thru power from that dash mounted alternator light is eliminated from the electrical system. (This is in reference to the page 7 & 8 comment referred to earlier).
I know that radiator fans when turning from the air passing thru the radiator while driving can induce a small current into the system, but I would guess he is stopped when turning off the car….
Oh yes.... I have also heard of that dash mounted alternator light picking up a ground source from the dashboard - So try removing the bulb in the Red light housing and see if the problem disappears....
Stephan mentioned to me that he has already replaced the ignition switch. So it’s possible he connected the small red MSD wire to a hot post on the new ignition switch. I’m guessing the car runs till fuel pressure is depleted (assuming it has an electric fuel pump which turns off with the key)
Or the new ignition switch could be from a different manufacturer and wired differently than the original was or just faulty.
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