Place the trimmed pork shoulder, orange juice, lime juice, minced garlic, cumin, oregano, sea salt, and black pepper into a slow cooker.
Cover and cook on low for 7-8 hours or on high for 4 hours until the meat is tender enough to shred easily with a fork.
Remove the pork from the slow cooker and shred it using two forks, discarding any large pieces of fat.
Heat a large non-stick skillet over medium-high heat and add the shredded pork with a splash of the cooking liquid.
Press the pork down and cook for 3-5 minutes without stirring until the bottom is crispy and golden brown.
Warm the corn tortillas in a dry skillet or directly over a gas flame until soft and slightly charred.
Divide the crispy pork evenly between the two tortillas.
Top with finely diced white onion, chopped fresh cilantro, and thinly sliced radishes.
Serve immediately with lime wedges for a fresh citrus squeeze.