Use your tractors loader/forklift and chain to lift the mower onto its side. Much easier to takeoff blades and stump jumper. Easier to remove blades before stump jumper.
good videos mate, got to burn those clutches in start of summer after sitting in winter. back off the spring tension bolts and let it spin in the housing by engaging the clutch and disengaging it a few times or as much as needed to burn in and release it if its stuck from sitting with water and rusting up like yours did. then set the tension so it grabs and spins
PTO driveshafts on our farm are greased up so they don't rust together. Just don't go crazy with it so you don't flick around a lot of grease when you spin them up for the first time. Usually just pull them apart and brush on some new grease when we grease up the joint bearings anyway.
If you'd like to keep the cutter from rusting through completely, keep the top of the deck clean. All of those sticks, leaves and dirt, when wet, will rot the deck out for sure.
Bushhogs get more damage by being left outside in the weather than anything if a person can't put one in a barn or shed get a good tarp keeping the rain off of one will stop alot of the rusting up
