Rub the pork butt all over with the spice mixture.
Grill the pork butt over indirect heat, with the grill covered and the vents fully open.
To help keep the meat moist, fill a small metal pan with the water, cider, and orange and onion slices and place it under the meat to catch the drippings and provide steam.
If your grill has a thermometer, keep the temperature of the grill at about 350°.
Barbecue the pork slowly, turning it occasionally adn adding coals as necessary, for 2 1/2 to 3 hours, until the meat is very tender and shreds easily with a fork.
Remove the pork from the grill and wrap it in foil; let meat rest for at least 10 minutes, then slice it across the grain, pulling off and discarding any large chunks of fat.
Using a large knife or Chinese cleaver, chop the sliced meat into 1/2-inch chunks.
While the meat is resting, you can fry the tortillas--heat the oil in a saute pan over med-high heat.
Fry the tortillas until crispy, about a minute per side; drain on paper towels.
On the plate--set out the crispy tortillas, a platter of chopped pork, and a bowl of pico de gallo (in a small bowl, toss together the tomatoes, onions, cilantro, jalapeno, and lime juice; season to taste with salt; best used the day it is made).
Allow everyone to make their own tacos.
You can set out bowls of sour cream, diced avocados, chopped lettuce, cooked pinto or black beans, and grated pepper Jack cheese.