Remove non-shreddable core from shreddable outer parts of jackfruit pieces; set aside. Remove any seedpods from shreddable parts and add seedpods to pile of cores. Place shreddable jackfruit in a medium bowl, and shred with your hands into small pieces. Finely chop cores and seedpods until they are a similar texture to the shredded jackfruit; add to shredded jackfruit in bowl. Add oil, 2 ½ tablespoons orange juice, cumin, oregano, salt, black pepper, and crushed red pepper; toss to evenly combine.
Heat a large skillet over medium. Add jackfruit mixture; using a spatula, press into an even layer. Cook, turning and pressing occasionally, until seared and golden brown, 25 to 35 minutes, adding oil as needed. Remove from heat and stir in remaining 2 1/2 tablespoons orange juice. Season with additional salt to taste.
Place about 1/4 cup jackfruit mixture on each tortilla. Top with a drizzle of salsa, and any additional desired toppings.