For the cabbage: In a large mixing bowl, combine the vinegar, sugar and salt and mix together well. Add the cabbage and stir to coat everything evenly. Allow to marinate for 15 minutes. Fold in the cilantro and set aside until ready to use.
For the fish marinade: In a large mixing bowl, combine the tequila, cumin, garlic, lime juice and some salt and pepper. Portion the fish into 1-inch cubes and add to the marinade. Set aside to marinate for 4 to 5 minutes.
To cook the fish: Heat a flat top grill to high and coat with a little oil. Skewer 4 to 5 pieces of fish on each skewer. Place the skewers on the grill and cook until the fish is white and cooked through, about 1 minute on each side and about 4 minutes total. Remove the skewers and allow to rest.
Warm the tortillas in batches on the grill for about 2 minutes on each side. Remove the tortillas to a towel-lined foil pouch and cover loosely to keep warm.
To build the tacos, drizzle a little Cilantro Lime Crema on a tortilla. Top with some strained red cabbage mixture and then place a skewer of fish on top. Slide out the skewer so the fish stays on the taco, and then finish with more lime crema. Garnish with some crumbled Cotija and hot sauce and serve with a wedge of lime on the side. Repeat with the remaining ingredients.
Cilantro Lime Crema:
In a small bowl, combine the sour cream, milk, cilantro, garlic, cumin and lime juice and chill for 1 hour. Season with salt and pepper. Yield: 1 1/2 cups.