Might be worth looking into this......
In 1981 I had a 1969 Charger with a 383.

At night the lights were always dim, turn signals would blink slow, and I always had a faint burning smell in the car.
I really didn’t understand the charging system that well back then, but even at like 2500rpm, with the lights going the voltage across the battery wasn’t even 12.5 volts.

I brought the car to a shop that specialized in auto electrical.

The problem was the ammeter had become a resistor...... and the more current you tried flowing through it, the more resistance it had.
They just piggy-backed the two wires onto one terminal, bypassing the gauge....... no more charging problem....... and no more burning smell.