Has anyone ever personally ground out the thermactor boss seen just inside the exhaust port of a small block head? Given how much room it takes up, and how small the port is there would seem to be the opportunity to get a pretty decent gain in exhaust flow by eliminating it. Since I have the needed tools I could handle it. That is as soon as I get my valve springs off. Being double springs my standard compressor doesn't seem to depress them at all.