400 stroker

This is not a big deal.

You're going to mill the block anyway, right? So mill the block to 9.957" zero deck (-.023") instead of 9.980", mill the heads for 75 cc (What's that, about .018"?), use an .039" gasket and settle for 10.37:1 compression? I don't think you"ll be able to tell 10.5:1 to 10.37 compression difference. Oh, and you'll most likely have to mill the intake manifold and/or head intake surface a total .050".