It's my understanding that early production 68's had no vin on the engine. My 68 RR has no sign of, or provision for a vin on the block behind the left head. 68 383 identified on pad by distributor. Glad I have all tags!
My post was meant to point out all of the locations a VIN could be found on a "B" motor! There is talk that it's a 383, but with no casting date, not checking ALL of the locations a VIN could be stamped on a motor, you're just guessing! Just by the casting date alone, that will tell you what model year the block is from! Then you simply have to know where to look for the assembly stampings and assertain what the motor is! The casting part number on the left of the block will show the displacement, further narrowing the possibilities of where the motor came from!! Hey, best case scenario, the motor is a 68 383, possibly making it the original motor!
Same with the trans number, it will tell you the application of the trans according to the number! If it's a 68 B body trans, it could be original, if it's from a 72, not so much!! Things like this I would be doing like right now to help clear up this should the need arise!!! Geof