Reply to "Questions: Indicator Lights and 3G Alt wiring!"

First things first check the battery with a capacity/battery tester and make sure you have good connections on the pos and neg cables.
Battery in the front with engine in the back is a long cable run so the battery has to be strong with good cables. A must !
A prolonged 75amp charge rate will probably damage the battery and is a indication of a bad battery.
A 75 amp charge rate means that the alternator is working it's butt off creating a lot of heat and back EMF that could be why the belt is slipping.
Bypassing the amp meter will only eliminate your ability to monitor the system but do make sure the connection on the back are good. Disconnect the battery first !!!
The switched wire feeds the alternator field through the indicator lamp to excite (start) the alternator. If the lamp burned out you couldn't excite the alternator field/ start the alternator. Thus the wire with the resistor. It's a backup in case the indicator lamp fails.
The light should go out when the alternator comes on line.
Do Not short the field wire to ground to test the system. You'll have a runaway alternator and probably damage you electrical system.
The system operating voltage should be approx 13.8 volts warmed up. Much over 14 and you are nearing the danger zone.
Remember that you a dealing with 40 year old wiring so be gentle and look at it closely for damage.
Make sure that the v-reg is correct for the alternator.
My guess is you have a weak battery and or bad connection.
This came from my old brain, not a wiring diagram but most systems a built alike. Even so look at the diagram.
If all else fails return the system to it's original configuration and it will work fine.
Be aware that cheap alternators are just that. Cheap Chinese junk.
Be careful... Large cables means a lot of current.
Good luck.