Your changes all depend what you are looking for. Best set up without getting too loud is to remove first 2 baffles and drill 3rd but not sure where the catalyst is in the 07s. When removing baffles if you see a honey comb don't beat on that it's your catalyst and is soft so it will just squish closed. It can be removed but no need to if you like the sound with it in. I personally would go Freak rather than airbox changes. I believe the engine breathes better but I know some will argue that.

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