Just finished up installing a set of '04 48mm forks on the '03. Why is a kind of longish story I won't get into just now, but the main reason I undertook the project was to get a set of offset clamps on the bike. They're on order now. If you ever decide to do something like this, it was a near bolt on. The thing that missed was the steering stem. The forks themselves were from an '04 YZ250F. I resprung them with a pair of .46's and I'm going to try the valving out this weekend (the previous owner had them redone for SX/MX so, we'll see). The problem with the stem is that it was about a half inch shorter than the '03 450 stem. I'm not sure whether this is because it's an '04, or because it's a 250F. Between both bikes and both years, they list 4 different lower clamps and frames. But, both bearings are the same, and the dimensions of the bottom section where it presses into the clamp are also identical, so I simply swapped the stem from my old clamp to the '04 clamp, and everything else dropped back in the same place it came out of. The same thing could be done with '05 AOS forks, even if the clamps should turn out to be too hard to adapt, by using the '04 clamp set (same clamp diameters). I'll be back with a ride test.