Plug Hole Insert

[GALLOWAYISLANDS]

I Have A 1984 16 Foot Star Craft Walk Thru. My Hole Where You Put The Plug Is Coming Loose. Or I Should Say The Metal Insert Where You Put The Plug In Is Coming Loose How Do I Fix This? How Do I Get The Old One Out? And Should I Get A New One? Or Do I Reseal This And How Do I Do This? Thanks.