[Mark_C]

Those month ending VIN numbers are the VIN reported by GM in their end of month shipping paperwork. Essentially they are the highest VIN of the cars in the lot ready for shipping at mid night on the last day of each month. They are an instantaneous snapshot in time used to track production at the plants. I believe the list originally came from Colvin. The problem comes into play when comparing those VINs to trim tag codes. a Camaro took roughly 5 days to progress from a pile of body stampings to a completed car, so while a car with a VIN of 637016 might be sitting in the lot on April 31st 1969, it probably has a Cowl Tag of 04D, possibly 04C because it started through Fisher 5 days prior, and there is still 5 days worth of production coming down the line with April Trim tags on them (roughly 4000 cars). 67/68's are a little more straight forward because the the body numbers are fairly sequential to the VIN numbers, unlike the 69's which correspond to an order number that could have been assigned weeks before the build was scheduled.