1973 340 issues.

boy you did not read my post did you

Every word. You didn't explain anything in depth. The leakdown test is not really for diagnostic purposes like he needs. It is more of a tool to measure the percentage of wear on certain items. He will have much greater success simply pressurizing the bad cylinder with air.

A leakdown test certainly has its place. He has a cylinder though that would probably not even make a leakdown test register, so for him, it is a waste of time.