I thought window facia/cill boards were also hollow baz? they were when I used to fit them anyway.
Went through east coast fibreglass today and like you davey bought FAR too much gear, I bought 10 litres of resin, 2 Kilo of chopped matting load of woven roven and that silky smooth finishing cloth.
Now I need to think of imaginative uses for fibreglass lol.
Me and scho removed the gunnels and cuddy from the boat today so we could flip the hull over, put 5 layers of 480 gram chopped matting on from the outside (pieces shaped to hole getting progressively bigger, the end result once it sets will be thicker than the surrounding hull, once set I'm going to sand it down to be smooth with the hull then stick some of that nice silky smooth finishing cloth gear on, aswell as repair the keel sword which was the aforementioned 'minor hull work, but since I've removed the previous owners god awful repair job looks more major than anticipated, but that's in hand.
Once exterior underside of hull is painted I'm intending on slapping a layer of woven roven matting over the inside of the patched holes along with another 3 layers of 480gram matting,,, it'll end up being the strongest part of the hull. always best to be over cautious than under imho.
Anyway, patched holes when I left this evening waiting for resin to go off.

There is a noticeable bulge around the edges that's to be expected, and will be sanded down once dry.