340 Engine Cast Question

Airwoofer: the 71-1 i have has virtually no core shift. It was a motor home block.
The 71-2 isnt as consistant. Has a few cyls that are very close, if not into the cam tunnel at the bottom.
I would say -almost- any of the 70-74 360 blocks would be the ideal ones to use for 4"+ stroke.(if one is to use a production block) For a few reasons. Better metal, main bolt threads are blind, i have read/heard they have the same cyl bore cores as 340s, so would basically be a big main underbored 340 if any truth to that. Will have to start a new thread bout early 60 blocks.