We need a little more information- - - - -are you replacing a 3-brush generator with nothing but a cutout relay, or does your current system use a 3-unit regulator with the cutout relay, current regulator, and voltage regulator coils? What year is the truck? If it's got a 3-unit setup, simply replace the 6 volt generator and regulator with 12 volt units, using the same wiring connections. You'll need to install a voltage-dropping resistor on the fuel gauge, and also install a 12-volt ignition coil and reduce the running voltage on the coil to 9 volts with a resistor, and install a resistor bypass system for reliable starting. Swap out all the light bulbs for 12 volt items, and if you've got turn signals, you'll need a 12 volt flasher unit. If you've got a 3-brush generator, you'll need to do a complete rewire of the charging system, using a later-model wiring diagram.
Jerry

Last edited by Hotrod Lincoln; 12/31/2009 6:02 PM.
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