Loosen up the radiator bolts and just pull it back a bit. No need to remove it. It can be done with our moving radiator, but it's easier to move it
Where are you located?
No need to pull the trans. Remove the bolts on the left rear frame rail and pry it out. Put a piece of wood between the rail and trans. Pull the PTO valve out and use a torch tip cleaner to get the silicone out. It's going to be a small piece, sometimes it's hard to see
I'd bet a case of beer on the fact that you have something blocking the oil passage to the PTO clutch. It's usually a little piece of silicone gasket material.
There are 4 relays on the left side of the machine. Pretty much under your left leg under the seat. One of them is the shut down relay for the coils. I have seen several of those relays fail. If I had to guess I'd say that's it