Driving Project 69 Chevelle L78

[sixt9rsx33]

I just bought this driving project Garnet red bench seat four speed car. No tach, no gauges, no ps a stripper. The car came with the original engine running in the car, build sheet, wrong tranny. I got the NCRS shipping data report and it matches the build sheet. (I only have a partial build sheet) the options are listed but not the vin. So I am under the car today scraped off the gunk off the axle tube and am expecting to find a KK code rear end like what is on the build sheet but nope. I find a CF 3:31 code perfectly dated to the car. So my question is this. Were there mistakes on the build sheet, or were axle tubes mis labeled at times? I have not driven the car yet to "feel" if the car has a 4:10 vs. 3.31. I guess someone could had flipped out the rear end and the date just by coincidence matched the build of the car? I hope to have it on the road in a few weeks. I am not going to restore it just drive and enjoy a "beater". Probably just sell it after playing with it?

Thanks