Are you talking about the key for the torsion bar?
If so, you need a two jaw gear puller. Take the cover off, back the adjuster all the way out. Then put the puller around the mounting bracket for the bar, and put the tip of it on the key -- NOT through the hole in the block with the threaded hole in it you just removed the adjuster from.
Oh, make sure the front end is up in the air with the wheel off the ground and dangling -- that is, have a jackstand under the frame or crossmember, not the a-arm.
Now tighten the puller carefully, checking the seating of the jaws on the bracket. When you have the key lifted up enough, pull out the block, which Ford calls a nut.
Then slowly release the gear puller to take the tension off the bar. Once its fully down, you can remove the bar.