Remove skin from chicken and discard. Remove chicken from bones; cut chicken into thin bite-size strips to make about 3 cups.
Heat oven to 325°F. Heat taco shells as directed on box.
Meanwhile, in medium microwavable bowl, mix chicken and 1 cup salsa to coat. Microwave on High 3 to 4 minutes or until thoroughly heated.
Spoon about 1/3 cup chicken mixture into each taco shell. Top each with about 1 tablespoon each of the lettuce, tomato and cheese. Serve with guacamole and additional salsa.