The other day I had to get my Z06 worked on. The shop took off my rear spring and when they put it all back together the rear was riding about 3" to high. They lowered it after I took it back but they are just eye balling it. Could some other woner of a Z06 please measure the distance between your back side rocker pannels, both left and right side from the ground to the bottom of the pannel. Also your gas tank will have to be full and your tires at 30 psi to get a true measurement. Then measure from the top of your tire to the to the body. Thanks for your help!