I tried the HYDRA 740 wheels on my 850n/a, and was pretty sure they were rubbing just a tad on the wheel well, plastic and fender. The 20mm is noticeable, I had to take them off and replace them with the original rims I had on when I bought the car.

This answers the question what 850 wheels will fit on an 850, but what other models or sizes will fit on an 850? i.e. would a '98 s70 set of 15's fit?

Thanks for clarifying as to the rear fog lights. I am actually wondering about the most inner red light on the back of my sedan. Is this a stop light? or are they the fog lights? are they supposed to turn on when the brake pedal is pressed? if so, I'm in a difficult position because I don't see why ...

The lights aren't coming on when the brake is pressed down. The double filament bulb is, but the inside, stop/ brake/ fog, red light on my sedan, is not functioning. The diagnostics performed have been:
-I have checked what I believe to be most of the relevant fuses.
-no bulbs are out.
-replaced the ...

I am currently experiencing no rear "fog" stop lights, at least thats what I think they are called. The most inner two stop lights on my sedan... I have been struggling with my brake light failure warning lamp in the instrument panel cluster, for some time. I believe the bulb failure relay's are ...