Yet another header question?

Im going to be getting headers soon and when it comes to getting cats no cats or gutted cats i was wondering about emmisions? I live in Indiana and all they do for emmisison check is plug 96 or newers into a computer, they dont hook up exaust, so if I gutted my cats or got an off road pipe and then got the oxygen sims will the car still pass?? Or does the computer know or somthing? Sorry I have no clue on how the emmisions work.

i would get longtubes....
flp with removable cats.....i have them and love them and here in il the emissionbs are the same way....i already went and passed

i might as well have left the offroad pipes on cuz they didnt check it at all