I have a 2006 with stock pipes. It was too quiet so I read all the information on this thread which was very helpful.
I drilled the two baffle walls out like the great instructions and photos said but there was still a third that was over 10 inches in the pipe. I bought a second 12" extension and joined them together and drilled them.
I also drilled the 8 1/2" holes around the base plate.
Its pouring down outside so I haven't been for a big ride yet but so far I love the sound.
Thanks Very much
So you will have to use 2 12" extentions to do this mod on an 2006. Thanks