recently the bulb on my left fog light broke down. After removing the cover glass, it turned out that the reflector was very rusty (save for a layer of aluninum foil), and the bulb broke into pieces when removing it from the socket. Unfortunately, I've now got the back enclosure of the old light ass'y still on the car and can't remove it. It's held by a thick grub screw running from left to right and a small torx screw in front, which both fix the light on a carrier attached to the car body. I can't loosen the nut of the grub screw, not even with a big monkey wrench. Maybe it's also rusty.
So: How can I remove the old enclosure and attach the new fog light? The repair manual does not mention the fog lights at all.