I think that the heading says a bit but here are the details.
I have a 1994 Ford 2120 4WD with 2 stage clutch( and a safety cab).
Recently after a day of fairly heavy dung shifting the clutch developed some slippage which meant that getting the tractor back to its shed was problematic. Checking I found that the free play movement in the clutch pedal was 0 - so I adjusted it as per the manual and the drive gear was completely sorted but the pto is no longer capable of being disconnected by use of the clutch pedal. I haven't actually used the PTO since late autumn when it did perfectly good service driving a rotovator.
It is possible to engage the pto at low revs but it turns even when the clutch is floored. A friend suggested put an implement on the pto and then engaging it in the hope that the pto plate has become stuck by the face to whatever it rests on and could be freed by the shock - I tried this with a mower but just couldn't get the drive engaged - the same trick did work with a small water pump but that lacked the resistance to do much I think.

So I am wondering if anyone knows a trick for this. I've thought about finding a piece of equipment that has a neutral gear of its own which would enable me to attach to the pto and then bump the selector in against zero resistance prior to engaging drive on the device - nothing I own has this sort of characteristic but I suppose that it might work. The one thing that I desperately don't want to do is to replace the clutch - as far as I can see that would cost a US owner $2000 + for parts alone - past experience suggests that in the UK it'll be twice that . Any suggestions welcome - and I am aware of the dangers around PTOs and will only do things that don't kill people - I hope!