Fred,
92 500SEL... Eiback has some "Pro-kit" springs for $325. Part number 2529.140 H&R has non-self leveling springs for $299, part #29739.1 H&R's self-leveling springs are part #29739.2 and the same $299. Those prices/numbers are from Tirerack. http://www.tirerack.com/suspension/index.html

As far as if your car has self leveling...Look under your hood for a reservoir of hydraulic fluid. (compare the underhood pics of the 400E and 500E on this site, the 500E has the reservoir) There should also be some reservoirs in the rear. (I think) Pull up the carpeting + spare in the trunk and have a look around.

Hope this helps...Lee

[This message has been edited by Lee Scheeler (edited 06-08-99).]