I have done a significant amount of searching and cannot find answers to these questions. Truck is a 1961 B613T, 673 with a quadraplex, Does anyone have valve adjustment specs and procedures for a 673? I purchased a book that says to do it with the motor running. My preference would be to do with the motor off, so I am hoping there is an alternate procedure. I have been looking for rebuild kits for this motor and the only think I can find says "maxidyne convereted" Does anyone have any idea what that means? I am starting to see many posts that recommend not rebuilding this engine. I just purchased the truck and have not completely assessed the motor, I do know it is not the original motor to the truck, at least that is what the last owner said. But the blowby is pretty high and it was a working truck so I think the motor is tired. I am working on a restoration, but it will be as a personal toy for me more than trying to make it period correct. I would consider an upgrade in motor if it made sense. What would be the recommended motor for replacement? I would like to convert this to spin on oil filters. Any suggestions for a kit to do this? Thank You for your thoughts.