Add the pork shoulder to the slow cooker along with peeled orange, limes, onion, garlic, cilantro, seasoning and water. Cook on high for 6-8 hours or low for 8-10, until tender and easily shredded.
Add to a baking sheet and shred. Ladle a few scoops of the juice from the crockpot onto the pork to keep it moist while broiling. Broil for 2-4 mins, until edges begin to crisp.
To make the nachos: Arrange ½ of the tortilla chips onto a lined baking sheet and top with monterey jack cheese and ½ of the pork. Broil for 1-2 mins until cheese is melted and chips begin to crisp.
Add the remaining chips on top of the nachos and top with warm queso, remaining pork, cotija cheese, pico, corn salsa, pickled red onions and fresh cilantro.