Start out with a regular GT offroad H pipe. This happens to be a Pypes setup leftover from my '08 GT. It comes in four pieces: two halves of the H section, and two forward legs. You can buy these used for as little as $40 to $75 every day of the week. Discard the legs and you have this: Bring it to your local exhaust shop, have 'em chop out the X section and weld in the H section, including welding the crossover together. My shop did this for $50, including adding a bung before the cat for my Interceptor O2 sensor. You will end up with this: The forward legs match up exactly with the GT500 pipes, as do the rear legs. The shop said it was extremely easy to do, and the pipes required absolutely no tweaking. Let's say you buy a used H pipe for $75 shipped. Add another $50 for installation, and you have an H pipe for $125. That means that you could buy a new X pipe for $200, do the H section transplant described above, and have an H pipe for $325. That's a whole lot better than the $500 piece out there. P.S. - The opening in the Pypes H section is nearly the entire diameter of the crossover pipe, not a little tiny hole like I've seen in some other setups. By the way, the sound is absolutely worth it with my Stingers. Love it.