Once they are unseated, hold down on the retainer plate and remove the u-joint, then you can gently lift plate off of the guides.
Slowly screw the u-joint bolt out a bit, lift the retainer plate, and start working the brass guides up out of the chambers until the o-ring is unseated. Once you get the u-joint popped loose, work very carefully unscrewing it, those brass piston guides have springs underneath them, if you were to simply remove the u-joint and retainer plate, the resistance of the o-ring seal of the piston guides would let go and parts would fly. I have seen the u-joint installed with Loctite, making it all but impossible to remove it without destroying it, well, sacrificial part then, replace the u-joint. You can clamp the body in a vise, put a wrench in the flats on the actuator disk, and screw the universal joint out that holds the retainer plate on the top of valve assembly.
This is a pic of the re-assembled unit, as I didn't have a pic of the unit when it was removed. This may not be that unusual though, so note how you take one apart. I've repaired a couple of pilot valves, but I don't recall one being quite as specific inside as this one. After he disassembled it, it became clear to me the former shade tree wrench had not paid proper attention to what they had disassembled and had not performed correct re-assembly, which I thought would benefit others as to what I found inside the unit, and to caution anyone who attempts to take one of these apart to note or mark the orientation of the valve mounting and every piece as to where it came from. My helper removed this one from a Case 9050B excavator because it was working all wacky, it was obvious someone had been inside this unit and had done something wrong. Also, much more comfortable rebuilding while standing at a workbench than fighting one inside a cab. I prefer to disconnect from the hoses and cap or plug the hoses so the valve components can be drained of oil and cleaned. I've repaired them inside the cab with hoses still attached, and disconnected from the hoses as well. It's typically just a tiny u-cup seal for the pistons causing the leak, replacing that seal is the challenge.
From excavators to skidsteers, variations of this type pilot oil control valve are used on many machines nowdays, and the most common problem they have is leaking oil from the spool pistons at the top of the valve. Here's a component that has been mentioned at various threads and folks have asked what kind of project is it to repair, the simple joystick control valve.
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