rear ride height

I noticed the rear fender (top inside of fender well) on drivers side is setting one inch lower than right side rear fender. It looks like the only adjustment for this is the rear cross spring. When I adjusted it so the end of the spring was the same distance of the ground as the right side it made the ride height worse. I raised the end of the spring up almost as far as it could go and I still had 3/4 inch difference and the ride stiffness on that side was very hard compared to right side. Question is the spring just wore out or is there another adjustment some place to correct ride height?

When sitting on a level surface with a full tank of gas, the rear transverse spring should be almost flat with only a slight arch in it.

The factory service manual has checkpoints with measurements that can tell you where your discrepancy might be.

Thanks, I  could not find any measurement data in my shop manual but I did adjust the spring bolts so the top of the spring was the same distance to the bottom of the frame on both sides and the bounce feels about the same on both sides. The left rear inner fender gap is still off about 1/2 inch smaller than the right side for some reason but I know the relationship is correct to the frame.  Thanks for your help.

Hey my Friend,  Try going around the track the other way for a while. It may just need to be equalized from a different perspective. 

LOL, my racing days are over. 

The ride height information in my service manual is on page 5 of the specifications which is located at the very back of the manual. The target Heights for the Corvette are located on the preceding page at the bottom.