Are there updated instructions for deploying a FileVault recovery key in OS X Yosemite?

I'll admit, I don't yet know enough about the Mac OS X Keychain to be able to figure this out on my own.

I am able to set a master password and copy the /Library/Keychains/FileVaultMaster.keychain file to another place, as instructed in the advanced support article. However, I can't figure out how to delete the master password as instructed in the article.

The article states to `Delete the "FileVault Master Password Key" by highlighting it and then pressing the Delete key on your keyboard. Click Delete in the resulting dialog.`

When I try to do this, I am presented with two options, to "delete references" or "delete references and files". Neither option appears to do anything and the file does not seem to be modified. The Keychain also seems to be locked, and will not unlock when I press the unlock button. I'm never asked for a password to approve the unlocking.

Any ideas what could be going on?