Hi Daniel,
Our Drive/Spot lamps can only be used with main beam too. With the original wiring, current for both headlamps and drive lamps went through the dip/main switch - not good, the switch was never designed to carry that kind of current. I'm not sure it's that suitable (at least on older cars) to take the current for headlamps!
I have a 'classic' Lucas rear fog light to fit to RTA - came from a pal at work, it was on his grandfather's car.
Cheers,
