Toast the guajillo and ancho chiles in a dry skillet over medium heat, about 45 seconds per side, until fragrant. Cover with hot water and let soften for 10 minutes, then drain.
Blend the softened chiles with achiote paste, garlic, pineapple juice, vinegar, orange juice, cumin, oregano, and salt until completely smooth.
Pour the marinade over the sliced pork in a large bowl, toss to coat completely, cover, and refrigerate for 8 hours.
Heat a cast iron skillet over high heat until smoking-hot. Sear the marinated pork in a single layer, 2–3 minutes per side, until charred at the edges and cooked through (145°F internal). Work in batches if needed.
Add the fresh pineapple chunks to the same hot pan and char for 90 seconds per side. Chop the pork into bite-sized pieces.
Warm each tortilla for 20 seconds per side in a dry skillet. Layer rice, beans, pork, cheese, charred pineapple, and cilantro. Fold the bottom up, tuck in the sides, and roll tightly. Serve with lime wedges.