Screw the Cat. Just have someone tune the code out of your pcm. I think you can get a "Race Pipe" which is Catless from Summit Racing. I have a Catless Downpipe that I got from Hogan Muffler.

W Body GM

I got the DP2 Catless System. He no longer has it listed on his website due to the EPA getting after him. But if you give them a call they might hook you up.

Good Luck!