Just my two cents but I would hit the easy button get a set of flat tops close to zero deck and use the magnum heads to get the closed modern chamber and knock resistance that goes with it.
You know, I would be doing that if it were my build. My Dad, however, is married to the idea of using x-heads. He also has some money already dumped into these heads with a bowl blend and gasket and port matching with the LD6B.
With the KB domed hypereutectics we can get some quench back. Also, it’s about $200 to drill the Mag heads for the LA intake bolt pattern.
