Does your car still have the fender tag? It’s an embossed metal plate on the drivers side inner fender in front of the windshield washer bottle. It will have a bunch of codes (two and three character codes) on it. One of them is a scheduled production/build date. If it starts with a A, B or C then it was built in October, November or December 1974. Second and third characters are the day of the month.