The clutch slave is located near the clutch fork. If you remove the air box, you should be able to see it just fine. I would also replace the clutch master if you're doing the slave and the rubber line that goes from the hard line to the slave cylinder since those flex lines have a liner that will collapse on itself from time to time.
You said you "think" you need to replace it, what brings you to that conclusion?
All that being said, welcome to NICO!
