Some people use cloth and lay it opposing 45 degree directions; some people use chop strand which is what I prefer.what is the direction of glass fore aft or side to side, or both?
You have to think about the traveler not getting in the way of the port, I have seen others put it in the middle. Personally, I would agree with Mashmaster and attempt to address the crack from the outside first, unless unstable. If you grind down the gelcoat on either side of the crack about an inch or so, that should be enough to provide stability to anchor the new glass to, if that makes sense. And, being careful to not open up the crack any more than what is already there. You should spend some time looking at some Sunfish posts, seems like that group is always posting about their repairs. I don't know if it's because they are terrible sailors or the boats are poorly made or what? (Just joking ) You should be able to get some good ideas on how they repair fiberglass, a lot of their posts show some really good work and provide details.where do you put an access port on aft deck to access this