Steering shaft coupling

Tring to take the steering shaft off the steering box. I loosened the bolt on the bell coupling and got it to move about 1/2" but that was it. Do I need to pry harder or will it come off when I remove the steering box? I am removing the box because I can't get the nut to move as I try to remove the play in the steering. (Spanner nut on the input shaft) prolly going to replace the box with a j-10 or j20