Thanks for the bobweight and the weight of the crank when your able, that will help me out a lot. Which factory crank are you using on this build ?
So to keep the stock stroke and go to a BBC jrl, a .100" or so has to be removed from the jrl, but that's .100" or so from the top & bottom, and when you remove over .100" from the top of the jrl, the
oil hole moves toward the jrl radius, which can be an issue, so I stayed with the stock jrl size.
I am trying to keep from taking your Thread off topic.