Bert, Found it---Custom Automotive Machine Service--his name is Jesse--631-581-0042. The excellent machinist I used to use passed away a few years ago and a back up shop is no longer in existence. I called a few of the shops listed in the Yellow pages but was turned off because the only person I could speak to was a front man--my concern--how many people would the instructions go through before the actual machinist had his hands on the head? Jesse works alone out of a shop on his property and it turns out he was a good friend of Racer Jack, the deceased machinist -- they were competitors on the local circle tracks--Freeport, Islip and Riverhead. When I went through the tall stockade fence surrounding his property and saw chickens running around all over and his dog playing among them I immediately had a good feeling.
As for your concern over the "knock" in your engine (piston noise is ususally referred to as "piston slap") I'd be happy to give it a listen if you are out this way (Bay Shore). Engine noises are difficult to express in words--your "knock" may be someonelse's "tick"--etc. -- Dave