Here is another option from a company called Car Chemistry. They are a small company I think in Texas. I used their inserts at the header flange and it reduced the obnoxious bark of my exhaust. They have several options that might work for you. The inserts I used are suppose to work best if kept close to the header, but they have several options. The link below is what I used.
http://www.carchemistry.com/sh...?l=product_list&c=76
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