custom pistons, custom inlet manifold, custom exhaust manifold for starters. It has been done and it'd be pretty cool but it aint going to be cheap. As far as I'm aware on the actual head the only modification required it getting an extra oil or water way welded up. But the main issue is that the AFH head has combustion chambers in it so trying to use that with any g40 pistons which also have combustion chambers in them wouldn't work.