From what I can see, a few old tires. two boats with tow straps hooked to it and a couple guys on shore, should be able to flip it easily. If anything, I would jack it up or lift it and maybe put a tire or two under the shoreline side gunwales of it, then put a few out there to catch it once you flip it. It's already kinda angled to flip easily, with a few guys on shore to get it lifted up and going. Getting it off the shore will be a method of pulling it a little and moving the tires then, over and over again. The problem is to go easy with the pulling boats, something none of us are used to, lol.
(Pulled many a backhoe and bulldozer out of the muck, rivers, etc. even a few flipped backhoes)
Can be done with one boat, I would think, but the more the merrier, and easier. Be safe on this guys, stay clear when the boats are pulling!
Ray
Gawd this is exciting! wish I was there already!