I bought a 2000 929 and it was originally purchased in Hawaii and the mid pipe was broke off and I purchased one from cycle salvage and it has a threaded hole for 02 sensor that i plugged and a cat in it right before end pipe. ie: no wires for sensor. Hawaii doesn't require smog cert so the original midpipe probably had no cat. Should I take the cat out? How do take it out? Is the cat affecting the original tune?