In a small bowl combine the kosher salt and chipotle powder. Rub the mixture into the pork, being sure to cover the entire surface of the meat.
Put the pork in a clay roaster or other deep roasting pan with a lid. Place the covered roaster in the oven, turn the heat to 275°F (if you are using a clay roaster, do not preheat the oven), and cook until the pork falls apart when you press it with the back of a fork, about 3 1/2 to 4 hours.
Remove the pork from the oven and let it rest, covered, for 15 minutes.
Heat the tortillas on a medium-hot griddle, turning them frequently, until they are warmed through and soft. Wrap them in a tea towel and place them in a basket.
Transfer the pork to a large serving platter and use two forks to pull it into chunks. Add the lime wedges to the platter, place the cilantro in a small serving bowl, and serve immediately with the tortillas on the side.