i think you guys are actually talking about the same thing. i've heard it being refered to as a mid-pipe and a down pipe. On a GSR swap into a Civic, yes it's true that the header will not bolt right up to your car. I have seen different ways around this problem. You can either take your car to a muffler shop and have them extend your mid-pipe(the piping that connects the cat to the muffler) by about 2 inches or so, but i have also seen people extend out their cat. They will cut the part the flange is on and extend it out.