I looked in my trunk from the underside and cannot tell if the keel pivot bolt is SS or not. My lock bolt goes through the keel. The hole lines up when you winch it up a couple clicks past full down, basically just enough to take the slack out of the cable, bolt goes through, then I slack the cable so it doesn't make the whole boat hum.
The sides of the trunk are plywood cored. knock on them with a hammer. they should sound solid, not a dull hollow thud.
by observing the water line, my lock whole sits about 6" above the water and the pivot would be right above the waterline.
If I take it off the trailer this spring, I will lower the keel while the boat is on blocks so we can all look at it better.
If you have any other questions, or need to see anything else on my boat, feel free to ask.
These are fun little boats, but build quality and quality of materials are very lacking. Some where even kit built.