Does anyone know how this black sweeper seal is attached? It’s attached on the inside surface. I can’t feel any mechanical connectors. Is it glued? Fit in to a slot? Any help would be appreciated. It needs to be replaced. Also, how is the white seal around the outside perimeter attached? Seems to be glued, but I don’t want to start pulling on things until I know. Last question…where can I purchase these seals?