Have a 97 1 ton feed truck off highway only. Front driver side was sagging and hitting stops so told tuff truck what i used it for and they recomended their stiffest spring. Install went ok but realized i had a broken spring. Now that these monster springs are on ( estimated 3.5 lift) what can i do to rear leafs to level truck. I haul over 5000 lbs on hay bed regularly. I cut some failed airbags off truck when i bought it so dont want to go that route