I need help choosing a new set of rear springs. I have complete Roush suspenion set up on my car. ( which handles & rides great) The rear look of my car would be greatly improved if I could get it to squat down a bit in the rear. The Roush kit lowered front and rear equally about .5-.75 inch. I would like to find rear springs that have the same spring rate as the Roush's but will make it set .75-1.0 inch lower. Any suggestions?