I hope you have better success with your big bore than I had with mine. Mines a 06 and it never made it more than 10 minutes. the builder finally gave up, the transfers are to close together and when you bore it that big they get closer, it kept hooking a ring and tearing up the cylinder and head. The 03 is more like the 99-02 that is a pretty common 310 big bore.
Like the bike, got the parts to build me one, maybe this winter.