1. Rub roast with salt, and place in a lightly greased 6-qt. slow cooker. Pour beer and 1 can of pineapple tidbits over roast. Process chipotle peppers and remaining can of pineapple in a blender or food processor until smooth. Pour over roast. Cover and cook on LOW 8 to 10 hours or until meat shreds easily with a fork.
2. Transfer pork to a cutting board; shred with two forks, removing any large pieces of fat. Skim fat from sauce, and stir in shredded pork.
3. Stir together fresh pineapple and next 5 ingredients. Serve pork in warm tortillas with pineapple mixture and desired toppings.