I have a 1991 Chevrolet Lumina with a 3.1L V6. The timing chain broke and valves were bent. Instill of having to have the heads repaired, I brought a set of Remanufactured Heads with new valves installed.Yesterday I finally got around and installed the new heads. Today when I started to adjust the valves, I ran into the following problem. There is not enough threads on the Rocker Arm Studs to adjust the valves, while rotating the pushrods until valve lash is eliminated. I found out today that the original heads on my car came with rocker arm studs (valves) that were not adjustable. The rocker arm studs on the old heads are taller than the rocker arm studs on the new heads. How do I fix this problem? Do I need to buy some Adjustable Rocker Arm Studs to replace the Short Rocker Arm Studs on the new heads?