Jimmy,

I can't speak to the w116 SLS, since I don't know.

But you make my point exactly.

The low point to which the (unloaded) car drops when the SLS system is opened is a measure of the "quality" of the rear coil springs. The bigger the drop, the worse the springs.

Ideally, it shouldn't drop at all.

But, unless I KNEW it wouldn't drop I wouldn't open the SLS system without ramps (or jackstands).