I purchased the KD 3087 valve compressing tool and it works well. As I mentioned I had two ball studs that were collapsed. After removing the ball studs from the block they both returned to their original height and I was unable to compress them after they did that. The oil passage to both of these ball studs was open as compressed air passed through after pushing out the oil. It's not like this engine was one that didn't get regular service and there is crud in the oil passages- this engine has no build up of any type.
Of the 14 other ball studs I found 2 that would not compress when I applied pressure to the rocker arm on top of it. After rotating the crank ten or twelve revolutions I found several of the ball studs that would initially compress slightly were now rigid. It is difficult to make sense of these things.