By the way, replacing it is a piece of cake. You only have to drain some of the clutch fluid (and of course replace fluid and bleed after everything's re-installed)..
You'll see that there are two covers basically, an inner and outer cover. If you break the seal on the inner cover oil will drain out. After removing all the fasteners and the connected clutch hose from the cover, just put something small between the inner and outer cover sections right where the clutch hose attaches and pop the outer cover off. If you do it that way you don't have to deal with draining the oil.
Its somewhat required to have a dog bone style or O-Ratchet (if you ever saw that infomercial) along with an hex key in order to remove the nut holding the cylinder in place.
Just be sure to replace the O-rings for the nut and the pressure cylinder.