1. In a large bowl, combine oil, garlic, Worcestershire sauce, lime juice, zest and cilantro. Divide marinade evenly between 2 large resealable plastic bags. Place steak in one bag, seal and marinate in refrigerator 4 hours. Thirty minutes before grilling, add tuna to second bag, reseal and refrigerate.Salsa
2. In a medium bowl, combine avocados, onion, jalapeno, orange juice, olive oil and garlic salt. Fold in oranges and cilantro. Place plastic wrap directly on surface; refrigerate 2 hours.
3. Heat a gas grill to medium-high or the coals in a charcoal grill to medium-hot. Lightly grease grates. Grill steaks 3 to 4 minutes per side, turning once, for mediumrare. Remove to a platter and allow to rest 5 minutes before slicing against the grain. Sprinkle with salt.
4. Grill tuna 3 minutes, turn and grill an additional 2 minutes for medium-rare.
5. Serve sliced steak and tuna with salsa.