GRRREAT posts! 5 years later.... what was the answer Harold?
Also, Vikki: You mentioned the date code on the engine being later than the car build date. I'd like to check mine. Is it a Julian code I'm looking for? Here's a couple numbers I found I cant ID. Thinking I'm on to something?
Looks like C148 or March 14, 1968 to me.
1968 400 Coupe, verdoro green, black vinyl top, auto 1969 GTO Judge coupe, Carousel Red, manual 1971 Trans Am, cameo white, auto 1970 Buick Skylark Custom Convertible 350-4(driver), Fire Red, white top, auto 1972 Buick GS Stage 1, Royal Blue, black vinyl top, auto