Good advice from others - but I'd add that you should take a close look at all the linkages from the lever to the clutch while you're at it.
Those pivot points wear quite a bit and can get real sloppy. Over-sized pins are available.
That sloppiness can make the whole assembly feel like mush.
Obviously it won't have any effect on keeping the clutch from slipping, but it's nice to be able to feel the snap in and out so you can adjust the clutch itself properly.