c32AMG-DTM

I'm not exactly sure what you mean... OEM (Original Equipment Manufacturer) supply the factory, so aren't "factory MB parts" just OEM parts in an MB box?

If it helps answer your question, the rotors look exactly like the factory ones, however they don't have any MB stamps or part #s on them from what I can tell, and come in a box that says "MADE IN GERMANY" - but doesn't specifically say "MERCEDES-BENZ FACTORY ORIGINAL PARTS"

1Lop2K5C

None of the links above showed anything for a C55 specific.

JDC55

The only effective way to reduce weight would be to go with a two piece rotor iron friction surface and an aluminum hat, or using a carbon ceramic friction surface. The CCM option would be cost prohibitive so a two piece system would be the best bet. The last thing you want to so is reduce the dimensions of the original rotor. The Mass of the rotor has a lot to do with its thermal capacity, and you don't want to reduce that.

gaiex

The rear rotors showed all are for C55 and some other MB models that use the same rotor, but for the front one I only found for SLK350 with sport pack, aren't the same as the C55 ones? I read that somewhere else...