Unfortunately, I do not have the Vin sticker like you do. Mine is missing because someone had repainted the car at one point. however, my white 510 is made an 11/69, which makes it a 1970. and those hinges are different. they have the smaller arches like all the others. So my assumption is those hinges that are aftermarket are 1970 to 1973 only. From what DatsunMike said, based off of my VIN number from my 69 he assumes that it should be made between April to May based on the number.