Rivetnut Rant: I have my swimming ladder, for example, attached to the swim platform with Rivnuts, a kind of rivet that provides a thread. See mcmaster.com item 94020A364.
I like them because
1) You can fix a ruined hole because you overdrill for the rivet
2) The threads are in the rivet so you can bolt to deck, cabin side, etc WITHOUT access to the back side.
3) FastJeff uses them.
1975 32' Flybridge Sedan, twin Perkins 6-354 diesels, 1:1.53 velvetdrives, 16 X 19 props. Merritt Island, Florida