I appreciate all the replies. As I stated before my car does not have the original engine. The engine in my car is #5R09K244XXX which is different than my car and is date coded June of 1965. My car was probably built in April. The E5 balancer that I have is right for my engine but not right for my car. Since all HiPos have serial numbers it is immediately evident when a car doesn’t have its original engine. Thus, should engine parts be date coded to the engine or to the car?