rog use some denatured alcohol in a spray bottle and some paper towels to soak up the exess fuel the alcohol evaporates fast and breaks the fuel down for easy clean up it will help remove the fuel from the balsa then check your glue joints and if you find some loose ones use some thin CA glue to make sure the fuse is sound and all the joints are solid after finding a leak in my tank in my NEXTAR this method worked great for me. the covering was fine after my leak and clean up the alcohol the plane still lives to fly today.