The x pipe will come with o2 bungs. Just swap your current ones over. I've learned the hard way, only use oem O2's. you also may get a cel after the o/r swap. Either have the rear o2's turned off or have them deleted via tuner.
2005 GTO 6.6L,Twin turbo, E85
2010 GT500. Lethal ORX, stingers, eibach, JLT, VMP 2.5, VMP tune