Coenraad , a clutch that takes very low is not always a sign of a worn clutch plate. Usually a worn plate will take right at the top. Your problem sounds more like hydraulics or weak pressure plate (less likely). First check the level of hydraulic oil (it uses normal brake fluid) in your 'clutch fluid' reservoir (It's mounted on top of the clutch master cylinder). Also check around the master cylinder for leaks and against the fire-wall where it' mounted, as well as inside the cab under the dash where the linkage from the clutch pedal goes through to the master cylinder.
Get someone to depress the clutch pedal while you watch the amount of movement on the clutch fork at the slave cylinder on the bell housing, ... if there is full travel, then it's not a hydraulic problem, and more likely the pressure plate. In that case, replace both clutch plate and pressure plate as well as the release bearing (the box has to come out). Also check the spigot bearing for wear. Put some Copper-Slip on the tip of the spigot shaft when replacing the box.
Hopefully it's just something small like the hydraulics.
the rest is dangerous teritory for me...and all the talk of "the box must come out" 
