You can get to the muffler seal by peeling off the outside of the canister, and it should be right infront of you. Be Very Careful, and use a lot of water to repack the seals around it. Think of the water doing the job of grease on heim joints. ;D
~Bill
(For any of you that are new to the whole quad thing, Don't do ANY of what I just said. sarcasm can be hard to pick up in message boards. And I was being sarcastic)