1. Make 1/2-inch-deep slits on outside of pork; stuff with garlic. Combine cumin, oregano, and salt in a small bowl. Place pork in a 3 1/2-qt. slow cooker. Sprinkle pork on all sides with spice mixture.
2. Combine beer, chipotle chiles, lime juice, and adobo sauce. Pour mixture over pork. Cover and cook on High for 6 to 8 hours or until pork is tender.
3. Remove pork from slow cooker; shred with 2 forks. Combine shredded pork and 1/2 cup cooking liquid; toss well.
4. Layer tortilla chips on bottom of platter; spoon rice and beans over chips. Add meat and toppings. Serve with lime wedges.