Ford 5000 Dealing with a stuck clutch!

It was time to deal with one of the big issues with my new to me Ford 5000 (5200) diesel tractor. The issue at hand is the tractor will not shift into gear, other than low range, as if the clutch pedal was not being pressed, even though it is. This is a classic case of a clutch being stuck, a common issue when a tractor has been sitting for a long period of time. Some folks even use a block of wood wedged in place to keep the pedal depressed during long periods of storage. There are a few schools of thought on how to attempt to break it free, and if all else fails, the only recourse is clutch service that involves splitting the tractor, a job I hope to avoid in my lifetime.