I'm planning on getting a Motoria exhaust for my 01 tib off importshark.com. I'm also looking into headers. I know I want a 4-2-1 header, but don't really know which ones out there are quality. Any first hand advice on headers would be welcomed. Also by adding a header, I have to move the cat right? If I do this will I need a different cat, or will the stock one work with the exhaust and headers?