I would like to have my fog lights work without the head lights, so I can use them during the day as running lights. Can this be done without messing up the existing configuration, where the fogs go off when the high-beams are turned on?

JWest Engineering. Here.

Works like a charm. Installs in minutes.

on my '71, the fog lights can be turned on with the parking lights. the headlight buckets stay down.

po installed previously?

Or you can simply plug the fog light relay into a different fuse under the dash. Actually it takes movement of both the relay hot wire and the switch hot wire if I remember it right.

You don't need to buy something - although I am not knocking the product, and the wiring change is a simple matter of changing where spade connectors go. It took me less than half an hour.

The basic idea is to wire the fog lights from the head light fuse. Notice that the headlights go off when you turn off the key, but the running/parking lights don't? You want the fogs to do the same.

Then you just pull out the fog light switch and leave it there. Lights on when the car is on, off when off.

Thanks all - I purchased the JWest item.

For what you are doing it can be done with a simple rewire job.

http://members.rennlist.com/demick/fogrewire.html

actually it is a simple move of one wire on the headlight switch. That is where the power comes from to the fog switch. .
another neat thing to do is rewire the headlight flasher so it flashes the fog lights, not the high beams. . . that's a little more complicated, you need to rewire the headlight lever switch and add one wire to the fog relay. .
at the same time you've got the headlight switch pulled out, you can change the headlight motor "up" lead so the headlights stay down with just the parking lights on. . that way, you can run the parking lights and the fog lights. . . I did this so if I was driving at dusk, with the bra on the car, I could turn on lights without the doors popping up thru the bra. . .