ok well im about to start on my exhaust and well im seeing all these universal carsound cats, well my question is which is best for the 92 gs-r? im going with jdm 4-1 header and kteller piping 2.5in if that helps. im thinking maybe the 53006 any opinions? anyone have a similar setup? i need just a part number everyone says yea im using the carsound cat but they say no part number....