Thank you David.
Documentation as to the production plant and SPDs for the archives will eliminate a lot of “guessing” “think” and speculation in the future by substituting facts.....
Folks, if we don’t document and share what we can when we can, we will never get a handle on some of these details.
FWIW, the pertinent portion of my VIN is CM279KC, 1969, 440 350 HP, Jefferson assembly plant. 318 is the SPD, March 24th, 1969 was the actual build date if memory serves. I can NOT remember where I got that date right now.
719884 - build sequence number
I believe my car to be completely original with the exception of the carburetor. I got it with ~ 49,000 miles, has ~ 59,000 miles now.
The original owner replaced the Holley with a proper Carter 4640sa, that was a "thing" back then. The second owner claimed to have the original Holley, but it wasn't the one for this car.
I'd like to thank David for providing the definitive answer to the thread.