Heat gas or charcoal grill. In 1-gallon resealable food-storage plastic bag, mix marinade ingredients until well blended. Add shrimp; toss to coat. Cover; refrigerate 20 minutes to marinate, turning once. Meanwhile, in medium bowl, place bell peppers and onion; spray with cooking spray. Place vegetables in grill basket (grill "wok"). Wrap tortillas in foil; set aside.
Place basket on grill rack over medium heat. Cover grill; cook 10 minutes, turning vegetables once.
Drain shrimp; discard marinade. Add shrimp to grill basket. Cover grill; cook 5 to 7 minutes longer, turning shrimp and vegetables once, until shrimp are pink. Place wrapped tortillas on grill. Cook 2 minutes, turning once, until warm.
On serving platter, place shrimp and vegetables; cover to keep warm. Place warmed tortillas on plate; place guacamole in serving bowl. For each serving, top tortilla with shrimp, vegetables and guacamole; fold tortilla over filling.