The wire from your alternator, coming from your ignition/fuse panel, needs a diode on it -- note below:
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http://www.alanhorvath.com/54chevy/chevypics/wiring_1.jpg[/img]
The above is how I wired my engine area, bringing full power to everything from the firewall -- made a huge difference!
Before I did the above, my engine was running-on for a half-second or so ... after installing the diode, WOW - what a great feeling! When I shut the engine off, it really shuts OFF.
To read about the whole deal (above),
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