I don't think you're going to find better reference material than the WSM and some of the threads around here. Just take your time and think about what you're going to do before you do it. Most importantly make sure the engine is disabled (take out the glow plugs) and that both halves of the machine are well supported. If you get stuck ask (with pictures!).
A few pointers. Once the halves and supported and unbolted it may not want to come apart. I had to drop my sling a bit and let gravity break it loose, I then finished the job with a big screw driver.
You should be replacing the clutch disc and throw out bearing no question, should probably replace the pressure plate springs, and should be examining or measuring the pressure plate and flywheel for unusual wear and cracks. A good straight edge (carpenters square, level, ect) helps check for flatness.
When you're ready to reassemble you need to recenter the clutch disc before the halves will mate. They make tools for it but those cost money so here's the way I cheated. I bolted the pressure plate lightly to flywheel so the clutch disc could still move fairly easily and used the wiggle room that provided to get bolt the halves together. Then through the service panel in the bell housing I tightened the pressure plate bolts. One a time I removed each bolt, applied red loktite and torqued it down to the recommended spec. I actually resplit my tractor to do the last step but it's not necessary. Adjust the linkage and once satisfied put everything back together.
