High output alternator recommendations

Start at the basics.
1. CLEAN all connectors and ground points. If even 1 strand of the wire is broken at a connector, re-connector it with all strands in the connector.

2. Add a few new ground straps between the engine, frame, dash, gas tank and any other items.

3. Test for voltage drops.

4. UPGRADE wire sizes between all high draw items. The headlights should have been 14 Gauge but the factory used 18 gauge.
In 50+ years of high amp draws the copper has gotten smaller in true gauge, I measured my 65 B-cuda's at 20 gauge. I had been running 55w/100w H4 bulbs for 20+ years and the wires were always very warm.

5. REMOVE every Scotch Loc splice connector. My sons 74 D200 had 4 Scotch Loc's on the 10 gauge feed from the Amm meter and when I removed them, they had cut 7 strands of the 19 strands of the 10 gauge wire.

Anytime you upgrade the amperage output of the alternator you MUST do some mods to the Amm meter wiring. You can totally bypass it, not such a great idea, or do the partial bypass method of picking a large enough gauge wire to do a split load bypass like in the 'Taxi' system above. The higher the amp output, the larger the part load bypass gauge needs to be. Say you want a 120 Amp Altanator, the wire gauge need to allow 40 AMPs to flow thru the Amm meter and also let the remaining 80 Amps to bypass it.

Just as a note. If you go to a 1 wire alternator understand it gets its VOLT reading right at the field brush inside the alternator. If you have a major voltage drop in the wiring harness, the 1 wire alternator will not compensate as it still sees 14.5 volts inside. IMHO, a voltage regulator mounted on the firewall still gives the best true output. You can now get adjustable voltage regulators so you can turn a screw to raise or lower the voltage output.