Jaykc.. please exchouse that don't know all the english words , but
what I tried to show is the way I done such repair several times , ----
emagine you could find a simular boat and the owner was a nice guy .
Then you find the same area of his boat and simply make a small mold
covering the hole in your boat, so when you repair the hole you cast
the form from a simular boat. The important thing is to make that flat
mold in say two layers of glasfiber and resin , treadhis boat with the
right slip solvent -- usealy some water soluted agent that often is
plain carpenter glue and plenty of wax, before you start taking the
mold.
Such patch are easy temp. glued over the hole and as long as you dried
out the edges and angled them the right amount ,make the build up
repair cover the edge well , then such repair can be made so the boat
is as good as new --- but no cut corners everything need to be
perfectly clean and dry and the small cracks that will show just need
to be filled with a 2 compoment epoxy filler.