[Andy]

I found an old Chevy pick up box laying in the dirt.
I picked it up and was surprized that it not only turned but was smooth as glass with to slop at all. Perfectly tight.
Chevy used the same side steer box from 37 to 59 when they went cross steer. The same type internals were used in GM vehicles untill the R&P boxes.
They are recirculating ball design like a Vega or 60 Chevy or a 76 Corvette.
They look just like a F100 box to me.
I have a Vega in my 32 roadster and can steer it with one finger.
The pictures are of a 55-57 box
Just a thought.