swapping all of an 03 on a pre 03 frame

You'll need to cut/weld the mounts up front for the CDI/voltage regulator and hood/headlight mounts, and the mount for the rear hydro master cylinder. If you're careful, they can be cut off the 03 frame and welded to the older frame.
All else is the same.
 
you can mount the headlight by bending the front hood tab for the pre 03 frame up and mount the headlight to that

you will also need to zip tie the front mounts of the 03 hood or make brackets