IMO, a correct clutch job would include a resurface of the flywheel, new or rebuilt pressure plate, disk, throwout bearing and pilot bearing. Many professional mechanics will not do the job unless they do all this. You may get by with less.
Its one of those things where, "since you've got it torn apart you might as well go all the way"
It would be a shame to just slap another clutch disc in there and still have a nasty clutch chatter. I say, go ahead and pull the flywheel and drop it off at a machine shop to get resurfaced, buy a complete clutch kit and replace the disc, pressure plate, pilot bushing, and throw-out bearing. (pretty amazing advice coming from me since I'm the ultimate cheapskate....LOL)
All good advice. Another pearl of wisdom is to be sure and clean all the oil off the cover and the flywheel (and your hands) really well before bolting it all together. These trucks are already prone to clutch chatter under the best of circumstances, and you'll want every advantage. I finally went with a diaphragm style cover and solved all my chatter woes....
I would replace it all.
However I would try to have someone rebuild the parts you have.
With every thing being done over seas the quality of parts is poor at best.
You should be able to locate a shop that would be able to rebuild your pressure plate and reface your disk at about the same price or cheaper than getting some Chinese part. I would also reface the flywheel. I don't like pulling the trans. more that once so when I put it back together I want it to be finished,and not have to do it again due to some cheap part failure.
I agree with Ross check for an oil leak too! Oil on a clutch will cause chatter and will kill your new clutch quickly.
Back in the day you could get a clutch repair kit that had everything except the flywheel resurfaced. Get the flywheel checked for cracks and resurfaced at your local machine shop.
Ross and BJ - I didn't find evidence of oil on the clutch components but there seemed to be three streaks of "grease" on the outside (backside) of the pressure plate. I am unable to tell where the substance originated.
Would a parts store, like NAPA, be a starting point for rebuilding the plate and disc?
Ross, missed your query about "messed Up' referring to the disc. The pressure plate side of the disc was unevenly worn on the asbestos or whatever that stuff is made of. The grooves between the "pads" were nearly filled with what I assume is the scuffed off pad material.