Based on other 340 Swinger build dates and VIN numbers, it was determined that it SHOULD be a May 5th casting date. It COULD be another date, as long as the VIN numbers are correct and the engine build numbers correspond it doesn't matter to me what the actual casting date turns out to be as long as it was cast BEFORE the car was built. I just figured by posting the presumed casting date it would make it easier for guys to check the numbers on their 340 blocks.
