As I pulled off the alternator magnet housing, the source of the main seal leak became obvious. The leak was happening where the seal lip met the crank. No damage was visible, however, until the replacement seal arrives on Saturday, I won't be able to compare the old one and inspect for abnormal wear. No use jumping to conclusions yet, but I do think high crankcase pressures play into this one, hopefully going away after break in is complete. Stay tuned..