custom fitting RB header
 

does anyone think its possible to custom fit it to bolt up to my bonez cat....i dont want to take the bonez cat off...

my understanding from RB on the down pipe is that the header and/or downpipe are slightly longer than the stock pre-cats.

The header is WAY long. It will not bolt up to the stock setup, so if you want to run cats, you can get one from www.mazdatrix.com that will supposedly fit, according to RB. (emailed em about this same question). Or you can just buy the header, and get a muffler shop to custom weld in the components. Make sure that what ever you do, it is 2.5 inch pipe for an n/a.