Dash lights will not turn off!! 72 dart

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My version is linked early in this thread. Where I have the MSD power, you can connect your new harness
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With my '67 I choose to run a second alternator output wire in parallel instead of replacing the original R6.
Since I already had a headlight relay harness connected at the alternator, I kept that too. If it wasn't already done thatway, I would have connected at new distribution point (single terminal stud).
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Here's the diagram for the '73 B-bodies with 60 amp Fleet alternator & battery.
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Some more versions here

Another heavy duty approach was used on A-bodies with rear window defrost.
On those, the battery and the alternator wires were fed through a grommet in the firewall. The ammeter's R6A stud was the distribution point.
Four examples linked here
 
Lets take a winch or plow that gets run while the engine is running. I've only seen the wired to the battery positive - some of the other guys maybe have seen some other arraignments but this is typical.

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When the engine is running and the plow needs power, power is going to flow from the alternator which is producing at 14 Volts.
If the winch is pulling 30 amps and the battery is recharged, the ammeter will swing 3/4 of the way over to show 30 amps.
The alternator output is around 36 amps; 30 to the winch, and 6 to the ignition and field.
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That's 36 amps going through that spade type connector. Turn the lights on, step on the brake and its more.
That's 30 amps through the ammeter and the spade connector and the 16 gage fusible link. And for more than a few seconds.
These are the situations that will cause damage.

A normal vehicle of this era doesn't draw 30 amps from the alternator except for brief periods when recharging and other equipment is running.
Some typical current measurements off of an ' 85 Jeep at the end of this thread
 
And it's WAY over 36A when guys put big alternators on, and the battery is low, or as you say, big stuff like pumps, fans, big stereos, driving lights, winches, etc etc. A big problem around here used to be snow plow hoists

"Ma" knew this was a problem long about clear back around 70. Some of the "C barges" had shunt type ammeter circuits. AKA the ammeter had small wires to a light meter. And the big optional 65A alternators had modified wiring became known as "police/ taxi/ fleet" wiring. This partially routed the ammeter wiring around the bulkhead connector, but you still had the possibility of ammeter failure.
 
Just got done fixing the burnt wires and got my bulkhead connectors in, got everything ran and so far everything is good I did the parallel circuit but ran the 2nd wire from the output of the alternator to battery + I know the ammeter won't be as accurate I used a 4 gauge wire I tested the battery with my multimeter and it tested at 15.3v on the terminals, cannot keep it running for long yet because the compressor pulley is acting up
 
That would indicate there is significant resistance in the circuit not related to the alternator output connection at bulkhead.

The direct wire to the battery removes the ammeter from the flow to the battery. If done correctly it will no longer indicate charging.
Be aware that the direct wire also a direct path for battery shorts.
 

That would indicate there is significant resistance in the circuit not related to the alternator output connection at bulkhead.

The direct wire to the battery removes the ammeter from the flow to the battery. If done correctly it will no longer indicate charging.
Be aware that the direct wire also a direct path for battery shorts.
I went through and checked resistance was normal, once I was able to run it for a while and drive it, it has dropped down the highest I saw was 14.5v and on curb idle it was like 13.0 to 13.9 dependent on the engine speed

I did see that when I was researching it but I am running a voltage gauge

I do plan on adding in something between so that I won't have problems with that, so far driving it around it has fallen into normal range on voltage

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That would indicate there is significant resistance in the circuit not related to the alternator output connection at bulkhead.

The direct wire to the battery removes the ammeter from the flow to the battery. If done correctly it will no longer indicate charging.
Be aware that the direct wire also a direct path for battery shorts.
i figured out what was causing the high voltage, i had a defective voltage regulator i had bought a cheap 1 from autozone, found out how poor quality they are, it would vary anywhere from 13-15.1V it freaked out when i was driving the other day and tried sending 17V again so i quickly pulled over and shut it off but it had already fried that alternator, thankfully i got a lifetime warranty on that, i bought a mopar performance voltage regulator it was about 4 times as much but it has dropped the voltage down to 13.5 steady, ive only seen it range from 13-14.0V now, i also sanded off the paint on the back of the regulator and the area where it bolts and im going to add a ground strap from the back of the block to the voltage regulator bolt
 
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