And they would be right Richard. I checked my 124 CD and it indicated that also. Four different thicknesses for the front and three for the rear. Perhaps reducing the front pad thickness will help. That is about your only alternative.
If I may ask, what brand of springs did you use? I lowered (AMG) my '89 300E without any trouble. The rear sits approx 1/4" higher than the front.
92 Volvo 740 Wagon aka "Mutt mover"