Yeah man, that valve lapper is old school. I showed a friend of mine one of those and asked him if he knew what it was. He played with it for about 30 minutes throwing out wild guesses but he had no clue.
two steps forward and a one step back...... LOL... click click they go... :D
I've done a lot of heads..... If it should fail, I have another way.... using a drill and a rubber hose