We did it like this to align the forces pulling on the chainplate and spread them to the hull.

Plywood was reinforced with glass on both sides.
Steel was cleaned and sanded, them glued to the plywood with thickened epoxy.
A couple of layers of glass on top again so the steel is properly sandwiched.
Then the bulkhead was installed in the hull and fixed with thickened epoxy and glass tape.



Guy in the pic liked the idea. Phill Brander was the one who came up with the idea and layup.

With the setup you are working on I would worry about lifting off the deck as it looks like there will be some leverage working there?