There all kinds of reasons the clutch could be jumpy. I am assuming when you say riding of the clutch you are meaning it shudders. Actually I think 'riding the clutch' really refers to not letting the clutch pedal all the way out, so you are not fully engaging the clutch disc (very bad).
I just went through much bother with my throw out bearing and it is all clear in my head, so I will post some comments.
You want to adjust the clutch so that you have the correct amount of pedal movement and the correct amount of clearance between the throw out bearing and the pressure plate.
1. You must have some clearance between the throw out bearing and the pressure plate fingers. You can verify the clearance by pushing the rubber boot on the bell housing out of the way and looking in past the clutch fork lever. There are several reasons that you must have this clearance.
a) You want to make sure the pressure plate is fully engaging the clutch disc (squeezing it against the flywheel). If the clutch disc is slipping between the pressure plate and flywheel you will quickly burn up the clutch disc and burn your flywheel (ruin it).
b) if the throw out bearing is touching the pressure plate while driving it is constantly spinning. It is not designed for that and will wear out quickly.
c) If the throw out bearing is real tight against the pressure plate it could actually be causing the pressure plate to not be fully releasing and hence will do the clutch disc burn up thing. And wear out the throw out bearing too.
2. Use the clutch adjustment rod to adjust the clutch. See picture. The location of the rod is center of the red circle. Loosen a nut and then screw the adjustment cone nut in or out to obtain the correct clearance for the throw out bearing. You will see that if you screw the cone nut towards the front of the truck you will be increasing the clearance between the throw out bearing and pressure plate.
3. Inside the cab, under the dash, at the top of the clutch pedal (drivers side of the pedal arm) there is a round object (a bumper so to speak) that determines how far up your clutch pedal will rise. It has an off center hole. I found that I needed to loosen the nut and spin this so that the thin section pointed towards my pedal arm, basically allowing the pedal to rise as far as possible. This then moves the throw out bearing farther back from the pressure plate. Ford manual actually has a measurement you are suppose to take from the floor to the pedal. I haven't checked mine yet, but I drove the truck in today and am satisfied with the amount of clutch pedal play I have. I know I have the throw out bearing clearance correct because last night the wife worked the pedal while I did the adjustment.
