Believe it or not, A friend of mine smeared a wild boar that he was cooking with mayonnaise like you would a skinless chicken breast! He didn't feel like taking the hair off so he went ahead and skinned the whole thing instead. The mayo was only used on the back side while the cavity was prepped the normal way. The mayo actually helped to form a bark and seemed to help in keeping the pig from drying out. Of course he also had a couple of layers of aluminum foil under the pig throughout the cook and the pig wasn't that big, maybe 60 or 70 pounds. I'm not sure what temp he cooked at or anything but I thought that the mayo thing was a pretty good example of redneck ingenuity! Personally I like the idea of a layer of some cheap thick sliced bacon on top of a layer of foil for the pig to rest on. It seems like the bacon would slowly render and give a decent amount of protection to the pig? I personally have never done a whole hog but I thought that I would pass some info to you in case you could use any of it. Good Luck!