Yeah they are missing some complete records for some years from some plants, like either 67 or 68 Firebird Production from the California plant. The only experiance I have with getting numbers info for one of my cars was when I originally Purchased my 1973 Lemans Safari Wagon with the optional 4-speed Manual Transmission. When Jim saw it was a 4-speed manual, an option he was not aware of being offered in a Lemans wagon in any year, he took it upon himself to look up the production numbers. He then found out it was only optional from August 1972 thru October 1972. And they only made 12 wagons with a 4-speed. 10 with 350's and a Saginaw 4-speed, and 2 with 400's and a Muncie M-20. My car is 1 of 2.
Jim said it helped that it was only available for 1/3 of the model year, so he only had to look thru those months of invoices. But unless Jim or his son are interested in finding out about a specific options production numbers, we will probably never know them.
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