Mustang tumbler gets stuck in certain positions

Suggest fixing this before it breaks the key off inside the lock cylinder. Once this happens the job goes from a straight forward DIY'er to a nightmare.

You need to know if the problem is in the lock cylinder or inside the electric ignition switch.

If this problem is the ignition switch it will be because it's binding. The ignition switch is a DIY replaceable item. It does not require PATS reprogramming.

The lock cylinder is also a DIY replaceable item assuming that the old key still turns the cylinder.

If this were my car I would start by performing a visual inspection on the lock cylinder after removing it.

Did you fix the issue. My Cobra is doing the same thing. Thanks