Had my Drive Shaft blasted today in preparation to balance with the rebuilt 12 Bolt Posi with 4.10 gears. On the end of each end of the shaft is the casting number 3790024, a Chevrolet emblem and what appears to be another casting number 003 beside it. Is the number beside the Chevrolet emblem the casting date. Can someone tell me from the other casting number whether this is the right shaft for a TH400 behind a 396 with a 12 bolt rearend? I was told so when I bought it, but.....

the drive shaft from a M-40 (400) is 5/8 of and inch shorter than one from and (M-38) 350. if you have a turbo 350 shaft measure. good luck