Do a GOOGLE search for Mercedes spring compressor made by Klann.

A month ago I found a source for the correct plate/type compressor for approx. $800.

Note- Klann makes a "universal compressor" but doesn't recommend it for Mercedes springs.

http://www.samstagsales.com/klann.htm

Here's the links:
http://www.themotoringshop.com/products/springsafetydevice.htm

http://www.southernscope.com/Tools%20for%20Changing%20Springs%20and%20Shock%20Absorbers.htm

:-) neil
1988 360TE AMG
1993 500E