I believe PHS would be your best friend, their report will tell you everything you ever wanted to know. Their web site is [url]http://www.phs-online.com/[/url] It takes some research to determine how correct or numbers matching you car may be. Prior to 1964 ALL engine blocks were stamped with the corresponding vin number of the car they were being placed in, this makes validating 1964 and earlier Pontiac\'s engines relatively easy. In your case, you will have to decode date codes and Assembly plants.