Yes, you can replace the bumpers and side skirts with the "sport" model. The only caveat is with the front bumper - if you use an OEM sport bumper, you need extra parts to attach it to a non-sport car. Instead, you might look at some aftermarket "sport style" bumpers as they are typically made to fit without the extra bracing. Of course by the time you pay for these part sand the body work to paint and install them, you could trade your car in and buy a year or two newer C230 sport.