ok this probably sounds like the dumbest question, but i have to ask. how are catbacks installed? are they bolted to the cat, welded to the cat, or either? the reason i ask is because i bought a high flow cat but its a "universal" so it has to be welded into the exhaust piping. so i'm just wondering if there would be any problem welding a catback system up to my "universal" cat? thanks any help!