Help! Can't remove steering shaft

[Kens1990K2500]

I am trying to replace my steering coupler, a/k/a rag joint. I have removed the upper and lower bolts, and was sliding the upper portion of the shaft, downward. It moved about an inch down (see photo), but needs to move another half inch, before it is free.

Problem is, it won't move any more. I tried hitting with a rubber mallet; a slide hammer (which mostly slips off); and a pry bar.

What can I do next? I think the middle of the shaft is supposed to telescope in and out, but seeing how this is a 33 year old rust belt truck, I'm guessing the slide action is seized.

I'm thinking about taking a Sawzall and cutting through the rag joint, but I don't want to risk cutting into the splined shaft of the steering box. Am at a standstill now.

 

[Kens1990K2500]

I was premature asking for help. Finally got it off. I just needed to use the correct attachment for slide hammer; earlier, I was using an L-shaped attachment. This time, I used an attachment with two separate hooks (the hose clamp is to keep the hooks from pulling out). Took about a dozen good whacks, but success, finally. A cheap Harbor Freight slide hammer saved the day.

Hopefully, this helps someone else.