Spent some time today on this again, and what I see is part A on the trim ring is bottoming out on the rim because the circumference is too big. Now to figure out how to make it smaller. Could break the weld and that would give the ring someplace to shrink when you hammer on it or cut out a V every so often to give that part of the ring some flex. See pic next one down

7021876-DSC06766.JPG (137 downloads)