If, as you say, the goop that is in, or under, the cloth is rubbery, then it is not just a bear getting the fabric off. It will be another bear, possibly an angry grizzly, to get the rubbery stuff off the decks. Heat guns, solvents, (not at the same time) and a lot of determination might get you down to clean wood. After that.....glass/epoxy with some good paint to protect the epoxy from UV degradation.
That is a pretty little boat that may be worth all the exertion that it will take to make it good again. That is, of course, if the rig, board, rudder and all, are in useable condition.
Good luck and keep on keeping on.