MB uses point system. Each car has points assigned to it. For example, 420SEL depending on the VIN has 19 or 23 points. Take these points and add points for options:
3 points for sunroof etc....
Total points will give you proper springs/pads combo. To make it even more confusing, same p/n springs are available with red or blue mark, and require different pads. I suggest you stop by MB dealer and talk to parts guy, or give Phil a call.