The Stovebolt Site Forums The Shop Area Driveline Replacing seals on my Torque tube.

Yes
According to the manual you have to remove the entire torque tube from the truck.
Because you need to perform the necessary universal joint ball housing adjustment. Page 1 -- Page 2
The adjustment determines how many shims are needed to get the ball collar cork seal to seal correctly.
You do the adjustment without the cork seal in the ball collar.

I would split the intermediate bearing u-joint, unbolt the ball collar, unbolt the support bracket from the cross member, slide ball housing/torque tube back until it clears the front u-joint rear yoke splines.
Remove support bracket from ball housing/torque tube so you can access ball collar.
Then do the universal joint ball housing adjustment.
Install new cork seal in ball collar and place ball collar over the ball housing/torque tube.
Install support bracket onto ball housing/torque tube.
Intructions - page 2