Ride height is measured at the dealer by the deflection of the control arms and converted into mm. The Beissbarth alignment system at my dealer also reports this number. Ride height measurements in the alignemnt section of the shop manual (sec 40) are give in mm using one of these two methods. Therefore, they not very useful for someone without these tools.

The best that you or I can easily do is measure from the center of the star on the wheel to the underside of the fender lip. Many 124 cars are about 15-15.5" (front-rear). Lowering would get close to 14" in most cases. Early model 124s were about 10-12 mm higher than later models such as yours. So I would estimate that 14.5-15" front and 15-15.5" rear is about right. A fuel tank of fuel vs. empty is about 0.5" difference. Ride height from side to side may be ~0.25".

IF you carry a lot of weight or live in a northern climate, its possibly time for new springs, or at least new or thicker spring pads in the rear. IF your front end is too high as a result of some suspension work (for example) then that can make you rear too low.

__________________
Brian Toscano