Looking for advice. Daughter (7) bought me a pocket watch from a second hand store. The hunter case crown is missing a cap to open the front. It appears to be threaded. Essinger seems to have the right replacement part. I can't figure out how to get the stem and crown out. I think this is an old Belle Suisse 8810. Help? Also I know it is posted to wrong forum but this was the only non grayed out option.