Thanks Drew, this is helpful. I do have separate set of cone seat bolts with correct length for the OZ wheels for the E500E. I'll also search this forum as suggested, but are you thinking my front 18 x 8.5 OZ Opera wheels might need spacers?MSQ = That's interesting, I have that same set of wheels, excepting the rears in my set are 9". I have run 10" 285/35 in the rear although the wheel was a 2pc. SL wheel. I believe the ET was 28. No issues. Terry and others run this size. I believe the ET on the 8.5 OZ is 34. I can't remember the proper tire size with the best O.D. match for these. I want to say 245/40.
Stephan = I have not gone larger than 245 on the front. Again, I believe others have but I would expect issues/close tolerances.
If either of you are looking for a lengthy read search the many discussions on the subject and the accompanying issues with spacers and proper size and length lug bolts. Nearly all aftermarket wheels require cone seat bolts as opposed to MB spherical seat. Rear bolt length, which could be different for each wheel is critical at the rear of the 036 due to parking brake interference.
p.s. the rubber on the front 8.5 is 245/40 18's