OK - First get a 4-pin Bosch type relay that comes apart. Some do and some don't. Radio Shack #275-226 seems to work well if you cut the mounting tab off.

Remove the relay cover. On the inside of the relay solder a jumper from pin 86 to pin 87. It doesn't need to be heavy wire. Reinstall the relay cover. The last step is to remove pin 86 from the outside of the relay. Just bend it back and forth until it snaps off. This last step is important to isolate the low beam and fog light circuits.

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