dmsfrr, I interpreted that he can’t get the column to move. It could be the “jacket” or whatever you’d call it, or it could be the slip joint in your picture. What I can’t remember is will that outer jacket pull off a shaft stuck at the splines in your picture. Then he’d be able to get right at it. I had mine all apart to take to the chrome shop, but don’t remember the sequence.
The outer chrome cover over the steering shaft is normally clamped solid to the dash & pedal support bracket near the top, also clamped at the bottom to the steering box shoulder around that lower part of the shaft.
The parts that slide to 'telescope' are the two splined pieces of the inner shaft, after the chrome upper locking collar is loosened.
Removing the whole steering column assembly hopefully won't be necessary since the goal is just to get the telescoping function to work.
IF the lower/inner shaft splines remain stuck the steering column assembly can't be removed intact.
The turn-signal switch hardware could be removed along with whatever else is at the upper end of the collar & steering wheel hub. Then the chrome outer cover could be unclamped top & bottom and slid upward to expose the lower splined joint. Heat could be applied to help loosen those lower splines from each other.
I haven't needed to try that, was able to take the assembled steering column out with the steering wheel still on it. So I could remove the dashboard.
Another possible method
??? ...after the steering wheel, turn-signal switch and other parts (bearing?) are removed carefully attach a slide hammer to the steering shaft and use that to pull the shaft out.
>> This could be a bad idea and damage the bearings/bushings, gears and seals of the steering box.
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