I bought a T1R 63mm test pipe from someone on here recently -- quickshifting, who is a great seller if anyone else buys anything -- but I'm having a little fitment issue. He said that it should fit, but he has an '01 and I have an '06. When I took off the cat and compared it with the TP, the TP was probably 2 inches longer. I didn't know there was a difference in the components of the exhaust from AP1 to AP2?

what other differences are there besides the length of the cat?

 

my test pipe was a little different in size from the cat as well but it ended up fitting ok.