Preheat oven to 350 degrees. In a large bowl, stir pork, 2 cups cheddar cheese, mozzarella cheese, green chiles and sour cream together until blended. Pour melted butter over top and mix again. Set aside. Wet 2-3 paper towels and wring out slightly so it's not dripping wet, but not completely dry either. Open wet paper towels and wrap a stack of corn tortillas in the paper towels. Microwave 1-2 minutes or until tortillas are hot and pliable. While tortillas are being warmed, spread about 1/2 cup enchilada sauce into the bottom of a large baking dish. Take a hot tortilla and spread about 3 tablespoons of filling down the center. Roll into a tight enchilada and place into baking dish. Repeat until no filling remains. Pour enchilada sauce overtop the finished rolled and filled tortillas. Top with remaining 1 cup cheddar cheese. Bake 20-30 minutes or until everything is hot and bubbly. Serve hot.