1. Place eggs in single layer in large saucepan; cover with cold water. Bring to a boil over medium-high heat. Cover; remove from heat and let stand 20 minutes. Drain and cool.
2. Peel shells from eggs; discard shells. Cut eggs in half lengthwise; carefully separate yolks from whites, leaving whites intact. Crumble 4 yolks, saving remaining yolks for another use.
3. Combine tuna, yolks, celery, mayonnaise, relish, onion, lemon-pepper and salt in medium bowl; stir until blended.
4. Carefully spoon heaping tablespoon tuna mixture into each egg white portion. Place filled egg halves together, forming complete egg. Press gently to adhere. Repeat with remaining egg halves.
5. Cover and refrigerate at least 2 hours or up to 24 hours.
6. To complete recipe, shred enough lettuce to equal 3 cups. Serve eggs over lettuce with grapes.