Buy 276-270 LED at Radio Shack. It has a built in resistor and operates directly from 12V. LED's are polarity sensitive, so be sure to watch the plus and minus leads when you build your tool.

+12v<________+LED-______________>|<_______ \_________>Ground

Pin 16 ------------------------------Pin 7-------switch----------Pin 1

( can't draw with a text editor )

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Resistance is Futile.