Anchors to use on fiberglass exterior

[penguin149]

The stock exterior speakers on my 2019 TT are terrible. I plan to replace them with some 4" waterproof Pyle speakers with speaker pods. I'll cover/repair the original mounting holes and drill new holes for the speaker pods. What is the best anchor to use on the fiberglass exterior? Thinking butyl tape around the perimeter of the pods and then Lexel sealant to make it waterproof.

[ralph_day]

I prefer no speakers on the outside. Try earbuds for the benefit of other campers.

[deltabravo]

Some sort sort of sheet metal style screw works dandy. Stainless is preferred.

I replaces a bunch of screws on my RV a few years ago which I outline in this video: Upgrading to Stainless Steel Screws on my RV