The lower front spoiler section on the 97 is different from the 98, but on close inspection it seems that the outboard vents follow the same function. Looking at the C43 spoiler unit, which has the fog lights installed, the venting is different, coming from a more inboard location. When we had the C36, I investigated lower fogs for the C230, and decided to leave well enough alone.
1. The outboard vents are not purely cosmetic. so that ruled out that location.
2. Adding them would require a separate switch on the interior, and I didn't like that. (see #3)
3. Wiring them to the factory switch would be possible, but difficult to keep the bulb-out indicator working properly.
One other reason I didn't go for any "extra" lights was the fact they would not be factory. I am always leery of "rice" appearing stuff on the car...
1998 C230 "Black Betty"