Excerpt From -THIS THREAD-
I believe C.J. Batten cyl heads was instrumental in developing the high port exhaust for the Dyno Dons and Bob G's and Jack Roushes. Batten was at the top of their game then and were welding up and porting the best bow tie heads on the planet back then, besides all the othher stuff. Does anyone remember the six cylinder heads they made for Bruce Sizemore. They cut the center two chambers from three Boss 302 heads then welded them together to form an inline six head that bolted on a 300 block! Sizemore, formerly of Preperation H fame, did considerable valvetrain developement and terrorized the former checvvy stronghold of I and J/Gas.
This is one description but I also remember reading somewheres of cutting down 351C heads) same basic design as BOSS 302) for this conversion also.