2003 GT 2v w/ KB 2.1L...what size headers?

Hello,

I have a 2003 GT with a Kenne Bell 2.1L supercharger... was wonder what size longtubes would best fit my application?
...i cant seem to find any video's of this exhaust set up on the 2v mustangs anywhere for an idea of sound either. but im sure i'd love it.