sorry robot i meant cast not stamped. and 283 does not jive with the cast number of the block since 3970010 was used on 1968 327 and 1969-1979 350 and 1968/69 302, and if that S/6 (second vin digit) is an 8, it would make the whole thing go together really well, since 1968 would be a 327 and the heads are 1968 307/327 motors. any thoughts on the second vin/id digit??