I removed the HV
oil pump and installed a standard pump, and the problem seemed to abate, but not entirely. I also had a bad carb, where the coating inside the bowls was dissolving and clogging the thing up (intermittedly starving for fuel). Holly replaced the carb. In addition to this, I installed the factory
oil return trays under the rocker posts.
After about 2-3k miles (and a new carb), the plugs no longer fouled, and the engine just ran better. Now at about 4k miles, it runs better yet and uses much less
oil than before. I think when all is weighed, the honing probably was not done right, and combined with the high oil pressure and the bad carb, just made things intolerable. The car runs great at this time, getting better as I rack up the miles. A joy to drive now. I still want to tweak things, drop the jet size a couple numbers and maybe install new rocker arm assemblies. These cars are works in progress, and I'll continue to try to improve the whole package. Thanks for asking.