Thanks Allen, I think the rivets on the inlet side are what I missed.It has been a wile but if I remember correctly on the outlet side of the muffler there are 6 screws that you will remove. I pictured them circled in red. On the inlet side there are rivets that must be drilled out. Then the whole assemble can be pulled out of the muffler body. It is pulled out from inlet side of the muffler.