Oh yes, hornets can be nasty. Not only will they get in through the frame openings (end of the box rails), they can get in through holes drilled for wires, etc. Of course, if you seal all of that up, they might just build the nests on the underside of the sail box, or the underside of the framing.

I'm sure 99.9% of my problem stems from not using the boat enough. Same sort of issues with the RV, if it sits too long, critters have their way with you.

Mike