Best caulk for mounting roof rack
My fiberglass penthouse top is leaking and the water mostly comes out the drivers side front corner and moisture wicks into the night shades as well as creeping down the canvas. It has had minor stains there and on the passenger side from leak when owned previously.
The leak got much worse the past year when the entire original roof rack was ripped off clean in a wind storm. I had a thin coat of Rhino-like material put on top of the fiberglass roof at that time, then had entirely new tracks, rack, solar and rocket box remounted. It started leaking more soon after that.
I have been systematically caulking holes on the fiberglass roof and about the only option left is where the right and left tracks for the rack attach to the roof. The drill holes from the new and previous job are only slightly outside where the canvas attaches to the roof, but I am almost certain now these are the culprits, a poor caulking job around the bolt holes when they were installed. You can see he ran a bead, but it still leaks. The local specialists are nervous about messing up my roof even worse trying to get the old tracks off without damaging the fiberglass beneath.
I want to caulk all around the edges of the metal tracks and also make sure the recessed (bad design folks) bolt holes are caulked but still accessible so I can adjust the hardware above.
What would you use to caulk these parts? I have previously been using 3M Marine Adhesive Sealant 5200 for small repairs.
Also, any quick ideas for repairing small holes in fiberglass that doesn't use fiberglass? Holes are the old bolt holes in the top- I just want to plug them.
Thanks for the advice.