Combine sweet and sour mix with remaining ingredients. Place fillet in a glass, ceramic or plastic container and pour marinade over. Cover and refrigerate for 3 – 5 hours, turning occasionally. Remove from marinade and place on a rack to air-dry for 30 minutes before smoking. Preheat a smoker and place the fish on the center of the rack. Smoke at medium-low (150 – 175 degrees) until the fish is firm and glazed on the outside.