I didn't take the wrist pin out but instead took the assembly to an engine rebuild shop. They've been in business for years, 2nd generation, and seemed knowledgeable. He showed me where they usually crack and what I saw was somewhere else and was apparently a parting line from casting. He did say that sometimes the crank end-play or dampener can give the same sounding symptom and removing a plug wire can change the harmonics and sometimes make it go away. I just checked end-play and have .007 so no issues there. My next check is to take the radiator/condenser out and make sure the dampener is on tight. The dampener has been refurbished since I've started this project.
Dennis
