the 80 A alternator was also installed in the 126 300se.
Appreciable dimming of headlights with AC & headlights running were eventually diagnosed to the rectifier section of the alternator.
There are 6 main rectifier diodes and 3 exciter diodes working via the red warning light. if any of these smaller diodes goes marginally bad the alternator output is substantially reduced under load until rectified by replacement.
One indication may be a very faint glow of the warning lamp .

mak

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