Preheat the grill to medium-high and coat grill rack with nonstick cooking spray. Sprinkle filets evenly with salt and pepper.
Combine lemon peel, 2 garlic cloves, 2 tbsp of basil, 2 tbsp of parsley in a shallow bowl. Gently press both sides of filets into garlic mixture. Coat filets evenly with cooking spray.
Grill filets on rack, covered with grill lid, 5 to 7 minutes on each side or until fish flakes with a fork. Arrange filets on serving platter. Cover and keep warm.
Melt butter in a large skillet over medium-high heat. Add remaining garlic and cook 1 minute. Add remaining basil, parsley and the lemon juice. Bring to a boil. Remove from heat. Spoon sauce over fish. Serve immediately.