Simon,
I believe you boat has AJ hulls.....and if so yours is not the only one I know of, with soft working area decks, that is, theones between the beams
It may be prudent to take the decks off and check all the frames....and easier in the long run, than doing it "keyhole"
but in the long run....your call
enjoy it either way, and not that hard a job either way
David
I'd go with David if you look up "stingray deck repair" on thebeachcats.com you'll see the results of keyhole surgery by the previous owner of my old stingray. It works for a while but then can be a total mess. If you can work out how to get your decks off you'll find the rest easy just grind out the cracked foam and put in new foam. I added a layer of divinicell and glass under the decks for hardly any extra weight and bullet proof decks. If you get the prescarfed divinacell it easily flexes to the shape of your deck, just take the deck off support it upside down put in some cloth, some resin add your foam, some weight to push the foam to shape jobs done.
regards