I believe the "test" pipes are the same length in a 2+0 and 2+2. The main difference is the way the down pipe angles down and TT test pipes angle up where they connect. The H pipe is 4" longer on a 2+2 and the last flange to the exhaust tip is 4" longer and curved differently to flow around the gas tank.
If you have JDM down pipes the mount right up to a N/A exhaust with zero issues, minus the huge restriction, but it works.