Smog and headers are not related. So yeah.
You may be thinking of the EGR tube that is on our headers (and not on Fox's). You can delete the EGR and use Fox headers. Do your research, though. Deleting the EGR can screw up the way your car runs.
You don't necessarily need Fox headers to do an EGR delete, either. You could just plug the hole on ours.
Specify what you are trying to accomplish here. Are you running factory manifolds & just want to run Fox headers? Or do you just want to delete some crap?