I have a 1988 Coupe that I am changing over to a torque arm rear suspension. Lets say I have Koni double adjustable struts and shocks with M&M coil overs front and rear. I plan on using 325 lb. front coil over springs for the front. What rate springs would I get to match front springs for the torque arm rear? This car is my last project car and need to finish it up soon. Mostly street and lots of interstate with hopefully some track time. Thanks.