I would make sure the tune on that engine was optimum FIRST before I spent more money and labor. WHat kind of ignition curve is in the distributor? Where is the camshaft installed? Was a degree wheel involved?
I've got initial at 20 and have an FBO plate at 16, the cam was put in strait up, no degree wheel. I now have a degree wheel given to me and was going to use it for the possible new cam, if I keep the cam I have, I'll degree it.