Heat grill. In large bowl, combine bell pepper, onion and mushrooms. Sprinkle with seasoned salt; toss to coat.
Alternately thread meatballs, bell pepper, onion and mushrooms onto four 12 to 14-inch metal skewers.
When ready to grill, place kabobs on gas grill over medium heat on charcoal grill 4 to 6 inches from medium coals. Cook 10 to 15 minutes or until meatballs are thoroughly heated and vegetables are crisp-tender, brushing generously with half of the sweet-and-sour sauce and turning frequently. Serve kabobs with remaining half of sauce for dipping.