You shouldn't be mixing up the push rods the wear pattern is matched to the lifters & rocker arms. Also the push rods are different lengths depending on your dry rocker clearance. That's how the clearance is adjusted to specs. Pulling studs out of the case is scary you should of wire brush the exposed threads & soaked with a penetrating oil like kroil or mouse milk for a few days & many applications. You can pull any one cylinder off alone, you heat, bend & grind the cylinder wrenches to make them gain access.
