[boostenlebaron]

There is a lot you can do but only a few that you should do. It's almost a shame to start ripping these bikes apart now.
Leave the motor alone. Get a power commander and dyno tune it. Stock titanium Exhaust header is about as good as you can get, the viper can isnt the best but there aren't that many choices for a new can anymore so it's up to you.
Suspension is where you can spend some coin. Rear shock replacement is pretty much mandatory now. Front end can be swapped from a newer bike to get the radial brakes or you can put cartridges in the old one and get better pads and lines to upgrade the brakes. 750 calipers of the same vintage are considered upgrades.

 

[boostenlebaron]

No one uses the rear lol. I purposely kept the rubber line and stock pads so I could modulate it without worry on the track.
My front brake set up is 06 front with radial calipers, ebc pads, brembo r1 master, full floating disks and braided line. It's frightening how quick it stops.
My front end has an ohlins cartridge and sprung for my weight. Ohlins steering dampener rounds it out.
Rear is a Penske triple clicker.