Hmmmmm... Well. . beginning with a Dec '67 Calendar, 1Dec is on a Friday, 31st is on Sunday; Christmas is the only 'necessary' Holiday, which is a Monday. Leaving a total of 20 workdays, assuming no work on weekends or Christmas.
From CRG VIN/production listing: ---------LOS------- -------NOR-------
Nov-67 315860 6208 352898 15178
Dec-67 321968 6108 368090 15192
Assuming constant production over 20 work days, each day found 305 built.
By VIN: The last LOS camaro in Nov was 315860, first one in Dec was 315861. Last one in Dec was 321968 (total 6108 camaros build at LOS in Dec.67.). Your VIN sequence was 320097, which is the 4207th produced in Dec of the 6108 cars total that month. Yours would have been built on the 14th day of production that month, which was a Wednesday 20 Dec 1967.
The alternative means would use body numbers, and go back to the beginning of the production year, adding up the totals by the month at that plant, and seeing where your body number falls... ie. thru the end of November, LOS had produced 15860 camaros. Your LOS body number was 19362, which was the 3502nd produced in December of the 6108. ASsuming flat production during December over the 20 work days would result in your car being built on the 12th production day, or the 18th of December (a Monday). Obviously there are variables affecting the production rate during a month which affect this, but it's a fairly good guess that your car was built sometime early that week (18-20th of December).
This calculation can be based on VIN numbers or body numbers, which can yield different results. If I understand correctly how the plants operated, the BODY numbers should have been produced in order (but perhaps VIN numbers were not produced in sequence), so perhaps the body number approach is more accurate. I'm interested what others have to say about how they calculate this for Camaro production, especially Kurt S or one of the other guys knowledgable about Camaro plant operations during those days.