1967 Dodge Dart GT Power Steering turns all the way to the lock to the right

There's an alignment procedure for the valve bolted to the top of the steering box in the shop manuals. However, if it had been working ok, and nobody has messed with it, I would be wanting to find out "what changed," something stuck, worn, dirty, etc.

Free shop manuals:

http://www.mymopar.com/index.php?pid=31