When I first heard of the upside down turkey some years ago, I wondered why a couple of new, big sponges couldn't be used to grip and turn the turkey. Then again, I never got around to trying it out.....
I usually just take my biggest chief knief and drive it through the opening for the stuffing, and then use a carving fork to help spin it around. Probably could also use tongs, although I have never done this. Suggest doing it on top of the stove.