[T Scott]

I'm not sure what you have there. It looks like a piece of fender welt that was somehow inserted between the two cover pieces. The face cover, the piece with the stainless trim ring, has a formed groove or channel at its outer periphery. This channel accepts a rubber insert that prevents metal to metal contact between the two cover pieces and is available at most early ford parts vendors. Installing this insert can be a difficult and tedious process for two reasons. One, the profile of the rubber insert may be too big to easily fit in the groove and two, the groove or channel in a lot of cases is misshapen and deformed. In any case, once installed it is contained and not something you have to deal with every time the cover is removed.