I disconnected the u-joint on mine (it had bolts). But with the truck sitting on the springs in the back, it would tend to bind. You might be able to jack up the frame and remove that bind.
[on edit] Actually, since you have the torque tube blocked up, there shouldn't be a need to jack up the frame. Maybe lift the engine/tranny a bit and pry it forward. The splines may just be bound up just a bit from wear.
Last edited by klhansen; 10/23/2020 10:37 PM.