Now you know why the car was for sale. Sorry. Seriously though, if your car originally came with the hydrolic suspension you may be facing a good bit of work. I have a 500SEC USA version with no hydrolics and if I had a euro that had problems I would consider converting to springs. Most suspension parts from 500SELs are interchangeable with the SEC so if you can locate a non hydrolic SEL in a junkyard you will have all the parts you need.

Don't see why you are having so much trouble with the pump - usually the problem is with the accumulators.

If you are a do it yourselfer, you can search for SLS or self leveling suspension, learn about it and then decide whether to keep the SLS system in tact or replace with non SLS components.

There is one other item to check which is the mounting bracket for the rear end. This bracket attaches the rear end to the frame of the car and if that bracket is broken, you will probably eat the inside of your rear tires and the rear of the car will sit low. The part isn't that much - maybe around 50 bucks or so and the bracket attaches, if I recall with two 17 or 19 mm bolts.

good luck

lee backus