O2 sensor

ok i need to get a new o2 sensor on my 97 civic ex... i put a new header and cat on and the 02 sensor that was on the cat is now on the b pipe of the header... if that is the one that needs to be replaced...what do i tell the parts store...the one after the car???please help

All you have to do is simply relocate the O2 sensor from the cat to the b-pipe. Shouldn't need to replace it in the first place, but if you want to, it shouldn't matter to the parts store the location of the sensor just the model and year of car.

thanks man i appreciate it...