I may be wrong but I didn't think that bi-xenons were ever fitted to a 2002 c-class. Bi-xenons are just a more powerfull lamp but fitted with a moving reflector so when you flick main beam the reflector lifts and all the light is released.
Bi xenons can be retrofitted in a 2002 C-class without a single problem; installation will take approx. 2 hours and you will have to remove the front bumper to get the job done (don't ask me exactly how to do it, as I myself have never done it before).
Please note, that you will have to take your car to the dealer and get it reprogrammed to xenons present!