Looking to get a new cat-back exhaust . has anybody out there ever BUILT one instead of just getting a pre-made for Borla ,Ansa etc.etc.. The reason Im asking is I have a friend who can weld so Im looking to Build one but dont know what diameter of stainless pipe and muffler to use. Keeps the cost low and at the same time I feel like I did something different for my car. Im just worried it sounding soooo RICEY!!!!