Re: Keith, what car did you put the Eibachs on? Did you leave the stock shocks? Which spring pads?
I have a 2001 C-240. I put the wheels from a new C32 on it (17 x 7.5 and 17 x 8.5) and the Eibach springs. It sits about 1/2' lower in the front and 1/4' lower in the rear than a C32. There were no stock shim/spacers on the front, and the rear shim/spacer was the smallest #1 (they come 1 to 4), so it didn't have to be changed. I drive 25,000+ miles a year and wanted it to look good, but ride good as well. I had much negative input about comfort with 18' and 19' wheels, because as your wheel gets larger, your tire sidewall gets smaller, thus less give and flex and a rougher ride. Realize that you will still have to lower the car to get rid of gap between the body and tire no matter what, unless you put on larger diameter tires, which opens up another can of worms - speedometer error/recalibration, tire rubbing, looks funny, etc.