Finally got answer. Went to dealer and begged in parts dept. to see rotors side by each. Wagon rotor is 2.5mm thicker on scrub (rotor contact surface) cross section width than the sedan. Otherwise all other dimensions are exactly the same. Same parking brake shoe, same caliper, same bolt pattern, same hub thickness and same overall diameter. Only difference is the wagon rotor contact area is thicker. Hopes this helps anyone else wondering. So if you race go to the wagon rear brake setup. It will handle higher loads according to the MB tech due to the greater cross thickness. Also spoke with Race technologies in Cali (they handle Brembo's sport rotor and big brake business for N. America and was referred to them by Brembo Corporate in Michigan). I was told the sport rotor for the sedan will fit the wagon however the thickness of the contact surface is 2.0 mm thinner on the sedan version (12mm vs. 10mm). Part #s for this are wagon rear Brembo #25759 plain, sedan rear #25205 plain, sedan rear #35205 drilled sport, sedan rear #45205 slotted sport. so #2 is for OE replacement, #3 is for drilled and #4 is for slotted in their parts numbers. 1996-2002 W210 non 4matic sedan e320, 420 and 430 all share the same rotors. The wagons through 2003 share the same front rotors with the sedan. Thanks oh Lord for the input. I don't have stock so I was no help to him.