I was getting ready to use my new stethoscope and the scraping sound is no longer there. Since the balancer is removed I am going to replace the seal and clean up the front of the motor, and then put it back together. I hope the engine makes it through Drive Your Pantera Day which is next Saturday, 8/27.
My hunch is that the problem will come back soon and I will try to locate the source of the sound with the stethoscope.