Mark, a couple things you might thimk about. Because you are putting in a Nova rear, I am not sure if you care about a stock look, but look at a stock truck and the rear wheels do sit a little forward in the wheel well. If you want it centered you will need to do one of couple fixes. Due to the torque tube rear end, the mounting pin on the springs are several inches forward from center. A lot of folks say you can flip the springs end to end and the pin will be centered. You will have to press out and switch the bushings. I have also seen where you just drill a new mounting hole on the spring perch a few inches forward of center line. I did this with my truck. But I have it sitting forward a little for a stock look. Good Luck,
Steve O