I have a 90 4x4 with a 300 and i want to put clifford duel outlet header on it but the duel outlet has no smog hook up or o2 sensor hole I would rather have duel outlet so i could run pipes of the header to two seperate cherry bombs then out at 45 degrees. Behind the tires. We have no laws in kansas so i really doen't want to put cat back on it but i need to do something with the o2 sensor but my muffler guy says i need one cat the first one on for good gas milage but the o2 sensor is in front of the cat so does it have any effect please post back with ideas of answers.