Place pork in the slow cooker. In a medium bowl, mix broth, cumin, oregano, salt, pepper, lime juice, orange juice and beer. Pour over the pork. Cook on low heat for 6-7 hours. Remove from slow cooker and shred. Return to slow cooker and keep warm till you are ready to assemble the sandwiches.
Pre-heat oven to 375 degrees and line a baking sheet with foil.
Cut the rolls in half. Spread mustard and mayo over one side of the bread. Top with pickles, 2 slices of ham and 2 slices of cheese. On the other half of the roll, top with shredded pork. Place the sandwich open face in the oven and cake till cheese is just melted. Join halves together, cut and serve immediately.