If your interested in doing it yourself, I have a couple of videos in my "low budget 318 build" that would be relevant to what you could do in the bowl area. Bowl clean-up would really help take advantage of the bigger valves.
Yeah I read through your thread, actually it got me thinking about doing the heads myself once I got this far. I already started on the exhaust, they have hardened seats and a step left in the bowl, those are getting blended in as well. The painted part is what's left to grind off this exhaust bowl to get the hardened seat blended in, then I will open up the rest of the bowl.