The idea would be to leave the existing chainplates inside the hull and use them as backing plates for new chainplates that are bolted to the exterior of the hull.

I think your shrouds are at the rail anyway, and external chainplates would not look out of place on a traditional looking boat like yours.

Check this website for details of how they did it on a 36' mariner ketch:(nl)http://www.svsereia.com/ (look about halfway down the "about" page).

Some vagabonds seem to have internal chainplates that are bolted through the hull. If so, you could probably just use the same bolt holes.

This would save you the huge mess of cutting out the glassed in plates and minimize the carpentry needed.

Good luck.

JM.(nl)