IH 574 Clutch

Been reading posts on here for a couple days now, gleaning information on my newly purchased 1975 IH 574 gas tractor. Everything seems to be functional and working on it at first test, but haven't run it through all its paces yet. High hours, 7100, but has many new parts and was serviced before I bought it, not sure if its been rebuilt in the past. Original tin and paint, well-cared for by previous owner(s). My question deals with the clutch, which I have some suspicions on. I've read here, posted by JB, that the clutch should have 1/2 to 1 inch of something or other. Does that mean the gear should engage at the bottom or the top? Not sure what that means. The clutch on this tractor does not engage the gear until it is almost fully released. I'm assuming that that means the clutch is almost worn out. Any questions, comments, or suggestions?

(a few minutes later)..... OK, so I've read through the instructions. Free height adjustment seems pretty straightforward. Then I adjust free pedal travel to 1 3/4 inches. Does this mean the pedal will drop that far as I adjust? How do I tell if no more adjustment is possible? Will the thread at the clevis be fully exposed or fully encased in the clevis? Hope that makes sense.

Thanks mucho for any help, all youse ex-spurts.