It helps to sand the paint off the torque tube, and use a vise grip chain wrench or a strap wrench to turn the ball back and forth as you pull back on it. Once the ball is retracted, unbolt the U joint and jack the torque up against the cab. Be absolutely sure NOT to have the weight of the vehicle resting on the springs, as there will be a lot of down force on the torque tube. (Maybe that's why the ball won't slide?) Use jack stands on the frame to support the truck, not the axle housing tubes.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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