I cut the hide down the spine and around the back of the rump and then in the front ahead of the leg, peel the hide to the center of the chest. Then prop the front leg on my knee and take the skin off it to close to the foot. Remove front leg and shoulder, hide already off it. Plop it in the cooler and cut off the hoof at the joint. Then do the same with back leg. Then take out backstrap. Then I use a sharp straight edge hatchet and "snick" carefully through the ribs up by the spine. Peel them away from the guts and cut the diaphram at the same time. Got a nice rack of ribs easy and quick. Then flip the hog over and repeat. Done.
I bring a sharpening steel with me to do regular touch ups to keep the knife (I use Dexter Russell Basics and Victorinox boning knives) hair shaving sharp. If I can drive the truck up close to the pig(s), I use the top of the window (partly rolled down) for regular touch ups. I wipe the blade clean with flushable wet wipes before each touch up. For making the cuts down the spine and around front and hind legs through the hide, I use a folding utility blade holder with hooked linoleum blades. I use lots of ice and a couple double hand scoops of salt in each cooler, 110-130 quart size. I can get 3 average size pigs in each cooler and try to fill a cooler per night (3-5 hours of hunting).