1983 300D, or a 123.133 with a 617.952

Alternator only works right when key is OFF (red light on brightly) and engine is still running.

Off voltage: 12.8
Running voltage, key on with no load, idle: 11.8
Running voltage, key on with no load, rev to 3000 for one minute: 13.2
Running voltage, key off, headlights on, idle: 13.85

Any clues which wire or splice is funky?

__________________
James Marriott
2003 Buick Regal
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