Ok, for the benefit of others finding this thread: The 'goop' is construction adhesive (liquid nails) - yep, you read that correctly. Why? Because the housing/bore/hole in the plate is of poor quality. It will hold the bearing in place okay, but it does not inspire confidence that it won't riggle loose. It is cast so that there are ridges/splines that make contact with the bearing, rather than a quality machined hole that is a precision fit as one would usually find for pressed-in bearings. So, I did likewise and put in the new bearings with construction adhesive and knocked over the rim with a pin punch (as it was) to be sure they stay in place.
