I've got a '92 500E, so I thought I'd respond. As regards the wiper blade/arm, the extra length must be the arm since the blade's the same as my '88 300TE.
Now, about the auxiliary driving lights...the lenses are different (more clear)than those of my 300, so I think there's more to it than just pulling the reflector out...now, the bulb's are exactly the same, but the auxiliary's beams are very concentrated, whereas the amber fog lights are quite diffuse. I will sya that the driving lights work fabulous!
You may be able to convert to the 500E lens, and therefore have the driving light functionality. However, your car's wired different, such that the fog light switch will light the auxiliariesrather than the high beam switch as on the 500.