Ozzy, to do this "right" you'll either need to buy or inspect and measure the following parts. The throwout bearing, pilot bushing, pressure plate and friction disk. Since you have to drop the tranny, if the budget can handle the strain and you're going to keep the truck, there is a lot to be said for doing the "whole enchilada" now.
In addition to White Owl, Saturn surplus, Memphis Equipment, TNJ Murray and others have the parts. Shop around. I found as much as a 50% difference in prices when I did two clutch replacements this summer. Most dealers had some of the parts, but not all. You may need to place more than one order. A copy of Military Vehicles magazine is a great place to find dealers. (or Supply Line or Army Motors)
If the flywheel shows any appreciable wear, now is the time to have it resurfaced. There are several good threads in the archives about changing out the parts.
Good luck
Lance