As far as I know it was only the Nosecone/headlights that changed, the rest stayed the same.
There was a little bit more. And the foxeye came in 2002 not in 2003.
Fuel tank volume grew from 18 to 20 (in 2000) to 22 liters (in 2002).
Exhaust was lowered in 2000 to give a better seat position for the rear passenger due to lower footpegs.
And the passengers handle was changed in 2000 (resulting in a slight modification of the rear fairing).
According to the official part catalogue (at least avialable in Germany for everyone) there are 4 differnent part numbers for the frames:
1998 and 1999 5DM-21110-00
2000 5DM-21110-10
2001 5DM-21110-20 or 5DM-21110-21 depending on VIN
2002 and 2003 5RT-21110-00
So there should be more or less big differences between the different years. But also a simple change in the colouring might be a reason for a new part number. Maybe the black tone was slightly changed.