With the car on the ground and suspension settled, is there much suspension movement in the rear on the higher side? Maybe the wrong strut is in there and is compressed at that point. Are you sure that the springs are the same? Count the number of coils and measure their thickness. With the car in the air and wheels removed measure the distance from the wheel well lip (see Zed Head's pic) and the center of the hub. Are they the same left to right? If you push down on the wheel studs with your foot does it feel like the suspension has dropped all the way down? If the strut assemblies are the same length, the insulators on the top are the same length and the suspension is fully stretched then it has to be the strut insert limiting the wheel drop with the car in the air. Am I wrong? Chuck