Bottom end info?
'Kirk,
The last factory steel crank that I remember was in 71, as for the dampner. Sounds to me like the block and heads are correct with the dampner but the crank isn't. What you may have is a 318 crank which carries the same dementions as the 340 counterpart and they were internally balanced, but you'll have to check the casting # of the crank to be for sure.
BJR Racing