I have it. If it's the the loudmouth 1 you are talking about its essentially a muffler delete. It sounded decent but wasn't loud enough so I went with long tube headers.
'11 Red Jewel Tintcoat 2SS/RS L99
GM 1LE 3.91 gears
Stainless Power LT Headers w/ high flow cats.
CAI intake
SLP Loudmouth axel back
Tuned by Speed inc
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