I've had this vintage 1960's Lumax "2001" fog lamp in my possession for a while - an impulse bid on ebay, landed me a very lucky deal for $2.00. I've had the lamp mounted on the SAAB's bumper for a while, but never got around to wiring it in. I had a vintage fog lamp switch as well, I just needed to acquire the necessary wire and connectors for putting it on the car. Here's how that went.
I started by testing the lamp by running wire directly from the positive on the lamp to the positive terminal on the battery. Nothing. Bad ground between the bumper and the car body. So I had to add a grounding wire. The horn post was conveniently close, so I ran a wire from that to the lamp bracket. Now I touched the positive wire to the battery again - success! A good ground.
I decided to take a break at this point before wiring up the switch. Taking breaks is the most important part of working on old cars. Believe me. When I got back I ran a positive wire from the lamp through the firewall and under the dash, where I mounted the vintage Unity lamp switch. The switch is the sort that was common in the U.S. for decades, it clamps onto the bottom edge of the dashboard, contains its own fuse and holder, and connects directly between the lamp and battery. At the time there was no requirement for fog lamps to be wired through the low beam or parking light circuits as was the case in Europe. So I was going to wire mine in accordance with that tradition. Check your local vehicle codes, as this is not legal many places these days, or even 40 years ago.
Once the switch was mounted under the dash, and wired to the lamp, I disconnected the battery so I could run a lead from the switch to the battery. Here I added a fuse. I did not feel comfortable running a long wire directly from the battery, through the firewall, and to the switch, even though the switch is fused. If the wire got rubbed through where it penetrates the fire wall, the fuse in the switch would do little good, and the result would most likely be a fire. After that the circuit was complete and the fog light could be switched on.
Wonderful. Fog situation neutralized. A vintage fog lamp is nice way to add some period interest to any old vehicle, and generally not an expensive option either. While they look nice enough simply bolted on, they offer some usefulness when functional as well, and it's an easy project to undertake at home.