Preheat oven to 350 degrees F.
To make the marinade, combine the orange juice, lime juice, minced garlic, oregano, Sazon goya, cumin, salt, and pepper.
Remove the pork skin 3/4s of the way and make several 1-inch cuts into the pork.
Pour the marinade all over the pork except for the skin. The pork skin should remain completely dry. Make sure those garlic chunks get inside the slits.
Place the skin back in place, pat dry the skin with a paper towel, you want it to be extra dry. Season it with salt and pepper, cover it with aluminum foil, and bake for 4 hours. Once the four hours are up, uncover and bake for 1 hour. After the 1 hour, increase the temperature to 450 degrees F. and cook for 15-20 minutes or until the skin is nice and crispy.
Once the skin is crispy, remove it from the oven and let it sit for 10-15 minutes. Slice off the skin and set it aside. Shred the meat and place it back into the pan with the juices. Make sure not to get the juices on the pork skin otherwise, it will soften.
Cut the bread in half lengthwise, and then slice it crosswise into equal parts.
Spread the mustard over the bottom slices of bread.
Place the cheese slices on the bottom slices and then top with the shredded roasted pork, ham slices, and pickles. Butter the top and bottom of the sandwich and then place it in a cast iron skillet or a panini press.
If using a cast iron skillet, use a heavier pan, like another cast iron skillet, to press down on the sandwich. Cook for 3-4 minutes per side until the bread is golden brown and the cheese is completely melted.