Got the baler already to go, but had a couple problems. Ford 250, PTO shaft kept shearing keys. Tore into the flywheel clutch pack, quite rusty, clened up and re assembled. But couldn't for the life of me get the slip clutch on the PTO to come loose. Tried the heat, oil, more heat, more oil, BIG hammer. Nothing. I look through the parts manual and it seem the you just wrench the big nut down on it. Someone musta really been wrenchen. Anyway, got tired of messing with that, soaked it down good, and went a split a tire on the AC. Dry rote got to the center rib and the tube came bustin through. So I spent the rest of the day replacing front tires on the AC.

I have always heard to never apply any lubricant to a slip clutch as it defeats the intended slip action purpose. If you are going to clean off the plates once you get it apart I reckon that is OK but I would be afraid that penetrant oil would soak the plate material and then it would become "grabby" instead of a more fluid start and stop to the slip. Think of fluid soaked brake drum linings and how they grab.

Good luck with getting it broke loose.