the answer to your stuck key problem is call a locksmith any reasonably good locksmith should be able to remove repair or replace your lock and keep the key so it matchs the other locks on the car
When you get the doors open, take the door panel off (take out the bolts for the handle and the panel just pulls off) with the window up, you can take the clip off the back of the lock, disconnect the rod at the lock and pull the lock out. then take it to the locksmith(see answer above)
ANSWER
YOU COULD GO TO A LOCK SMITH BUT THERES A POSSIBILTE THAT ITS YOUR DOOR IF ITS YOUR DOOR YOU HAVE TO GO TO A Ford DEALER AND GET A REPAIR
What Year? The fox body mustang locks are easy to change. Take the interior door panel off and on the back side of the lock you have to disconect the linkage from it. Then there is a clip holding it to the door. Just pull that clip off and the lock will pull straight out.
There are a number of reasons why your door might not lock. You could have something stuck in the door for example.
how do I fix a electric door on a ford mustang
Stuck how? Lock? Door?
No.
push down on the button at the rear of the door where the window meets.
"My lock is stuck"?
What? Barn door lock on a Yukon????
spray with WD40 if that doesn't help replace the door lock
door car zipper key/lock window
You can not close any door if the locking mechanism is stuck in the locked position. You must first get the mechanics to unlock.
door lock actuator stuck,bad door latch if rear door has child saftey on a bad door entry handle.