Rear Spring Replacement
 

When replacing rear springs on a 1989 420 SEL, it seems advisable to also replace the rubber pads(shims), which come in 9.5mm 14mm and 19mm sizes. How does one determine which size to order? I'd like to have all of the parts before starting the job. Should one just order the 14mm and hope they are right, or go for the 19mm?

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.