Ignition Tumbler Question

My ignition switch/tumbler is bad because somebody tried to turn it with a big screwdriver.

I believe I know how to remove/install a new one, but can't figure out which one to order...

The only key I received is a Ford key stamped H-56.

Here are the Motorcraft numbers I have found so far-

Number 1, Cut Letter A SW2416
Number 2, Cut Letter B SW2417
Number 3, Cut Letter C SW2418
Number 4, Cut Letter D SW2419
Number 5, Cut Letter E SW2420

How do I figure out which cylinder to order?