this one is a steel crank, not forged, it doesnt have any large #s like that. its stored in by buddys garage, so i cant look till after 5pm. but i,ll find whatever #s there is. i,ll even bring my reading glasses!
Got nothing on that number also. I know that the crank flange is not a 350's. Looks very similar to a large journal 327 crank flange. If the main journal size is 2.45 its a large journal if 2.30 small journal. My bet its a large journal forged crank in a 67 camaro 350 block to make a 327. But like you said still a mystery.