I have recently purchased a 03 wr 450 for cheap with a broken kickstart shaft and cracked right side crankcase cover (as a result). I inadvertantly ordered 04 parts (case cover, gaskets, o-rings, KICKSTART ASSEMBLY). Compared new case cover 04 and 03 cover, all passages and openings and mounting points appear identical. Now upon mockup assembly to check all parts and fitment the kickstart assembly (gear, shaft, spring) fit nicely and teeth make good contact, but I found some interesting differences. The 04 kickstart shaft is larger in diameter as well as the opening in case cover. Fortunatly i ordered new seal which matches cover and shaft. But the 03 kickstart lever splined opening is to small. I have seen other post pertaining to this type of breakage but no one using 04 parts to fix. Now as I see it if I get on 04 kickstart lever I have increased the strength of kickstart assembly (I am assuming) . Has this been performed before by anyone else or does this sounds like a possible upgrade.