1. Preheat your grill or smoker to 235°F. If you're using a grill be sure you set it up for two-zone heat and cook your pork using indirect heat.
2. Combine the mayonnaise and 2 tablespoons of the Head Country Bar-B-Q High Plains Heat Championship Seasoning. Mix thoroughly, and place in the refrigerator.
3. Mix the Head Country Bar-B-Q sauce with the apple juice to make your mop sauce, and place in the refrigerator.
4. Remove the pork from its packaging, rinse under cold water, and pat dry.
5. Place pork on cutting board and coat lightly with the mustard.
6. Season liberally with Head Country Championship Seasoning. Be sure to coat the sides and ends of the pork as well.
7. Add wood chunks to the hot coals on your cooker, and place pork in the indirect heat zone for 2 to 2.5 hours.
8. After 45 minutes of cook time, apply some of the mop sauce to the pork using a basting mop or brush. Repeat every 40 minutes as the pork cooks.
9. After two hours, or when the desired color is achieved, remove the pork from the cooker and prepare to wrap it. I use tin foil to form a boat, but you can also use butcher paper.
10. With the pork in the tin foil boat, add about ½ cup of the mop sauce and the chopped onion. Insert the probe of your meat thermometer.
11. Wrap the pork as tightly as you can. I use 3-4 layers of foil and return it to the indirect heat of the cooker.
12. Continue cooking until it reaches an internal temp of 185°F - 190°F.
13. Remove the pork from cooker and partially unwrap, letting the steam escape. Allow it to cool for 30 minutes before thinly slicing.
14. Apply a generous portion of the mayonnaise and seasoning mixture to the top bun of each sandwich and set aside.
15. Assemble your sandwiches by layering slices of pork, ham, and cheese on the bottom bun. Place the sandwiches in a 350°F oven for about 4 minutes or until the cheese melts. Place pickle slices on top of the cheese, add your top bun, then slice and serve.