Waterproofing fiberglass

I have a 10' drift lite fiberglass drift. The storage boxes leak a bit and i was wondering what the best type of glue/silicone/epoxy is best and most durable for fiberglass.


Help! I'm trapped in a landlocked state.
If the boxes are fiberglass just like the hull, I would add a layer of fiberglass tape soaked in epoxy along the edges.