My notes: Rampside muffler Stock 5 3/4" OD X 17" long, inlet offset Inlet and outlet are oppositely offset from one another. Muffler pocket @ 10 1/2" wide X 6" deep, tailpipe cutout offset. I used a: Cherry Bomb Muffler #16803 Oval 13" long x 7 3/4" wide x 2" inlet and outlet offset