Score fish by making 3 diagonal cuts on each side.
Lay 1 (18 x 12inch) sheet of foil flat on a work surface, and coat with cooking spray.
Place fish in center of sheet; rub oil in fish cavity.
Sprinkle 1/2 teaspoon salt in fish cavity; sprinkle remaining 1/2 teaspoon salt evenly on both sides of fish.
Place lemon slices and next 4 ingredients (through thyme) in fish cavity. Wrap fish in foil, twisting ends to seal; place fish on grill rack. Grill 10 minutes or until fish flakes easily when tested with a fork or until desired degree of doneness. Discard lemon slices and herbs.