Rinse fish in cold water; pat dry. Sprinkle fish with salt. Place open butterflied fillets on a wire rack; place another wire rack on top. Secure racks with wires to clamp fish together (this will prevent fish from breaking apart during grilling).
Melt butter in a small saucepan; stir in lemon juice. Remove from heat, and stir in Worcestershire sauce. Set aside for basting.
Place fish on grill 4 to 5 inches from medium-hot coals. Baste once with oil. Grill 10 minutes or until fish flakes easily when tested with a fork, turning often. Baste frequently with butter mixture.
Carefully remove racks; place fish on a warm serving platter, and serve.