011-2013 Mustang GT500 Axle Back Muffler Kit Removal of Stock Mufflers 1. loosen the OEM band clamp at the muffler inlet joint on both mufflers. Refer to Figure 1. Figure 1 2. Remove the rear muffler hanger from the rubber isolator. Lower the rear of the muffler and slide the muffler upward toward the front of the car to remove from the front hangers. Repeat for the other side. Refer to Figure 2. . Installation of MBRP Inc. Performance Exhaust: Figure 2 1.