70 Dart shift column rotating???

If you took the shift lever out, then there is nothing to prevent that bowl from rotating, about 30 to 40 degrees total . If you pop the hood you will see the shift lever flopping back and forth in a window at the bottom of the column tube.
The shift lever is welded to the shift tube, and the tube is keyed to the bowl, and locked to it by a lock-screw..
If the lever is no longer in the window, then the lockscrew has fallen out,the shift tube has dropped down,and the bowl is fully free to rotate 360* or until the shift lever hits something. If the lever is no longer in the window, then the lower bearing must also not be in it's proper home.
So to realign everything, the bowl needs to be somewhere in its normal range of motion,and likewise the shift-tube, and then you push the shift-tube up until it stops,then rotate the two, until the top key slips into it's place in the bowl, and then continue pushing the tube home. If the shift tube has come completely out of the bowl, then you will have the additional chore of getting it back in first.
Next,there is a shift-tube lock-screw in the bowl which prevents the shift tube from falling out. It is accessed from the underneath next to the shift lever, and about 90* to it. Laying on the floor and looking up. you will see the access port. Tightening is by small allen wrench, IDK the size but looks like 1/8 or less. It looks like a special screw so if yours fell out, it will likely be laying in the bowl, under the signal switch assembly,lol.
And finally, the bottom bearing will have to go back up into the outer column tube and be secured there with the special spring-clip.
> But if everything looks hunky-dory, then the top key must have sheared. It's only held on with one tiny spotweld. But I can't imagine that ever happening.

Happy hunting.