Head advice , It has 346s which is going to need all valves.Which I don't think has harden seats. Should I look for different heads to have worked or buy some rebuilt 542 heads from Aero racing. Or some other vendor. The guy was told when he had it built that the builder install larger valves had Sixpack pistons, Which he got neither just flat tops pistons and upgrade valve springs.Just a big cam in a low compression engine.