Please refresh my memory, is the stock h-pipe for a 01 stage 3 the same as 99-01 mustangs in general?

Can't remember but somebody said the only difference is with the cobra h-pipes will only fit cobra's but all the others are the same. I've found a few used factory h-pipes (that have working cats) that I must get put back on my stage 3 and just want to know if they'll work.
Thanks,
Dave