To do it right, you have to pull off the clutch cover, and the clutch boss and basket too. which means draining the fluid and replacing that.
Its kind of a pain in the ass. Pretty sure you gotta pull the clutch off to get the shifter shaft out. And you gotta get the shifter shaft out to replace that seal.
Someone else chime in on this? Ive done it on a banshee. If its the same on a blaster, Im pretty sure Im right.