i have a 1993 mustang gt vert and one of the cats have broken loose internally in the cat housing. i dont really want to replace it with the cost of $100 labor and another 100 for the part. are the cats required on all production cars all the time. when i went to a muffler shop they would replace the two front cats with blank spacer tubes for $100, and the added airflow would be nice for performance and sound.