Has anyone found a build sheet in their Flint, MI Chevelle?

[Berg]

I have looked in my new 1970 SS396 Chevelle project and i'm not sure there is a build sheet present in this vehicle. The gas tank and rear seat have both been taken out of it so no build sheet there, the only thing I found was a trim code tag for the black bucket seat interior that was hidden in the seat back cover of the the drivers bucket seat. I have been searching for examples of Flint, Michigan build sheets and NOBODY seems to have them. Is it possible there was a memo put out at the plant that no cars were to leave the assembly line with a build sheet? Since I don't have the original engine does that mean that I won't be able to verify my car as a true SS unless I find the original block with VIN or partial VIN and CTW code. I'm at a loss. I wanted to put this car in the SS registry. All signs are pointing to this car being a real 1970 SS396 350HP car with TH400 and 12 bolt rear. I have one more shot of checking the door panels and maybe in the headliner or under the carpet. i still have not totally taken the seats apart but I couldn't see anything stuffed in the springs. I'd think even if the mice got to it there would still be a remnant of it. I know they also weren't required to be put in cars but a lot of them found their ways into them anyways. I'm keeping my fingers crossed that I can prove it is real. I'd also like to find out what dealership it came through and if it was local if there were dealer records still available. I hear about sometimes these folders are found with the original owners name and original sale sheet and key numbers and all that good stuff. I'm still not giving up hope.