you should ALWAYS counter-sink the hole a bit in gelcoat. It will help prevent it from spider-cracking

I use a hole punch in masking tape. Placed over the hole, before caulking or marine epoxy, keeps it neat.

This was extremely helpful! Thank you!

Can you suggest or recommend a non-adhesive sealant for this application besides silicone?

counter sink hole and use bedding compound, not silicone

nice video yoy covered half of it

What if I wanted to use these snaps in my car the hold drapes against the windows into the plastic portion what adhesive would I use to keep the screw tight into the plastic. ?? Working with the Subaru Outback back window covering

Why would you use a rivet over this ?

Have you ever had to remove old bad rivet studs from a boat?

Not Silicun but Silicone

the one into the wood was fine except use proper caulking, not silicone, the one into the coach roof looks dodgy af - is that a composite deck? A better idea would be to overdrill the hole and fill with epoxy, let it set sand it back then drill into the epoxy, then install your fastener into that.. then you know you wont rot your deck when it leaks and please don't use silicone.