Well I have my engine out and if I want to port the manifolds, now is the time. Is this something I can trust a good machine shop to do? Or is it something that needs to be done precisely by learning from experience? The machine shop that I have been recomended to mainly work on older "hot rods" and I doubt they have worked on MN12 exhaust manifolds. If not, who do I go to, is there a certain company that works on MN12 exhaust manis?? Would it even be worth it to port the manifold with my mods below?