Well, i have a 2005 gtp and am looking into buying TOG headers. I dont want to replace my stock Cat. since i replaced it 300 miles ago ;-/ and have the stock exhaust still. I need to know if the TOG headers will bolt on w/ no problems and if the O2 sencer will not cause any check engine lights to come on. If i get it done at a local Mr.Muffler, would there be no problems with the computer? Please help. Thanks.