JoeDude, if the pitman arm fails to move until the steering wheel has been turned 3 inches, something is wrong inside. Maybe...maybe it could be an adjustment but 3 inches is quite a bit. As others have said your pitman arm should move when the steering wheel is turned even a bit. Try this: pull back on your steering wheel...that is to say pull it back toward you and see how much play exists. It should not move at all, but let's start there.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end