It doesn't take much water at all to field dress a pig. Mostly, you make it dead, hang it up and poke it so it leaks nicely then let it all leak out. Then it could be transported somewhere else or gutted and skinned there. If it was already hanging to leak, then it's handy to just dig a hole under it, gut it, skin it and drop the head, skin & innards into the hole unless you are saving them. Sometimes the intestines are saved for sausage casings, sometimes they aren't. Generally, the heart and liver are saved for at least dog food if not liverwurst or sausage. I've tried tanning the skins before, but our climate isn't nice to leather so it seems a lot of work for not much reward. Some people like cooking the pig's head as well as the feet, but usually there's so much of it that those get tossed into the hole along with the rest of the oogly bits. Shovel some dirt back into the hole and things will grow really green there later.
Generally, after all this, a bucket of water is enough to clean everything up with. Carcasses are amazingly clean and tidy, especially after you've already let all the blood leak out before even starting anything. If your only reference point is Hollywood epics, you'd be amazed at how little mess butchering can be.
The only problem I have with this is the timing. Six in the evening is just before dark and taking a pig apart is going to take several hours from the time it's down until it's in the fridge and everything is cleaned and put away. Is there any way you can trap the pig and then shoot it in the morning? I have a pig trap if anyone is coming from this direction and wants to relocate it. Then after the pig is caught and it's daylight, it can be shot & processed and everyone will have time to get there and get prepared. The other thing with traps is if the first shot doesn't drop the pig in it's tracks, it doesn't zip off into the brush and need to be chased for half a mile while it's bleeding all over the place.
If any of you want to get the carcass and bring it over here we can deal with it here. There's a guest room if things go too far into the night. In a perfect world, someone shoots the pig in the head (keeps the meat much nicer if there's not holes blown in it), then hangs it and bleeds it, then brings it over here and we can finish the process in a lit area. Skinning a carcass in the dark sounds like a good way to end up with less fingers.
If none of this works and folks still want to have a pig butchering lesson, I can set the trap up over here and catch a pig to practice on.