When traction bars were put on my car, original bolts were removed. I have a set of z shocks, part number 3192851. In the picture the bolt is not the same as what is sold as the rear shock mount bolt. Bolt on left is a repop, middle is original. Shock shows welded in stud and it does not have the solid metal collar like the bolts. Jerry's book picture matches my shock. What is the deal with these bolts. Were they used on replacement shocks?