Are you sure it's the rear shaft you have removed, the picture is of a front shaft? I have pictures of my front shafts along my rebuilding of the friont suspension long ago, it's the same as that.
That front shaft is very small, you can wrap any fingers around it. The rear shaft is much larger, about 3" in diameter, and longer, maybe five feet long. The rear shaft will have a flat flange at the rear that bolts to the diff.
Below is a picture of my front shaft, for my 98 Mountaineer, and the custom shaft I had made to replace it when I install a true 4WD TC, the BW4406 TOD version. Note the rear part uses a double cardon joint, which the stock rear might have in it.
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