I went the BlueGauges option on my '01. I sent them my dash unit and they changed it for me. I also went with a speedohealer rather than a yellow box but it can certainly be done. Keep in mind, the swing of the arm on the speedometer cannot be changed (due to the gearing of the speedo) so the speedohealer/yellowbox can only compensate for so much. For example, I had mine dyno-tuned when all was done and it's pretty much dead on until 80mph and then it begins to be overstated after that the faster it goes.
Suzuki Illumiglo Faceplates