I just used an ez lip they are like 25 bucks its just a piece of foam glued on. Its tricky to get it placed right i goofed it up the first time and ripped it off luckily it was still sticky and the second time came out better. I might take the tips off again and try to make them merge with the actual muffler tips better though. I hate the way you can see daylight when you look in there. Ive been trying to think of something to put in there to close up that space safely