First, did you try to adjust the cable to see if there's any life left in the current clutch? If it's toast, it's no big deal to change the plates. Drain the case oil, then pop the clutch cover off the case (round cover, right side of engine, behind the front part of the rear brake pedal-might have to remove brake pedal too to get the cover off). Next, take the six bolts off holding the pressure plate on the clutch pack. A spring comes off with each of these bolts. Take the plates out and keep them in order. There might be a special plate or two in a certain position, usually the inner most plates. The new clutch and friction plates will need to go back in the same way. Put the springs/pressure plate/bolts back on, then the outer cover and brake pedal if you had to remove it. Next, adjust the free play in the clutch lever. Do this with the barrel adjuster (either down by the case or just down the cable from the lever. First, I like to turn the quick adjust at the clutch lever to full loose, then take up the slack with the barrel adjuster. This lets you gradually take up slack with the quick adjust at the clutch lever without breaking out the tools for the barrel adjuster. You don't want to use up all of the quick adjust and have nothing left there so you don't get stuck without tools for the barrel adjuster. I like to adjust so there's just the smallest detectable amount of freeplay in the clutch lever. Fill her up with oil before starting it!
The shorter version of all this is, if you just start taking it apart, it's pretty easy to see what's going on. Keep your parts sorted, and reinstall them in the opposite order you took them apart and you'll be fine. :thumb:
Here's a pic of the guts in my 426 clutch: Click (Note the two special inner plates)