Yup that has been misunderstood by many, myself included.
Until you get down there and start Fn with it you wont really understand, but basically...
with the retainer off and the rod pulled off the WG pin,
Hold the WG closed and position the adj rod just in front of the pin,
looking through the hole in the WG adj rod you should see most (7/8 ) of the pin, but some light should be visible though the area towards the front of the truck.
This would mean to put the WG adj rod back on you'd have to pull it towards the rear of the truck and it would be very tightly holding the WG closed.
If you can just slide the WG adj rod on and off with little effort it is not tight enough.