Do you have hand rails inside the salon as well, or just on the cabin top? I just have them on my cabin top, and there are stainless machine screws installed in the handrail (with heads covered by teak plugs-or I suppose they could just be studs-I never had them out). The threads go through holes in the cabin top and washers and nuts secure them from inside the salon. Then there are white plastic covers that go over those holes. I used butyl tape on the studs and feet of rail to seal the holes. You could use some kind of goop in the alternative. The E25 doesn't have a headliner - just inside layer of fiberglass and gelcoat. If you have interior handrails, I assume you'd have longer studs in one and secure w nuts through the top of the other rail, and teak plugs for both.