I use the GM C130 alternator on a couple of swap applications and this is how mine are hooked up. If you purchase an aftermarket connector it will have 4 wires on it a red blue yellow and white wire. You will use only three
Blue wire -this is battery sensing that goes to the battery terminal on the alternator
Green Wire- This is your 12 Volt ignition source.
Yellow Wire - The connection to the charging light which limits the input to three volts or less. If you have applied twelve votes here you've instantly destroyed the alternator
White wire -not used
This is pretty much what Joe has said. I just added the caveat that if you have mistakenly applied much more than 3 volts to the Yellow (charge light wire) your alternator is now toast,
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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
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87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
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