Wow, that's a nice looking truck. If the steering is a bad as you said, the restoration was a skin only job. It looks like it has the original wheels or at least very similar, so the drivetrain is likely stock.
The AD series truck steering gear is pretty stout and not really prone to wear in the gears, as there's very little movement relative to the shaft nut and sector gear. The shaft nut doesn't rotate with the shaft, but is a recirculating ball design, and at worst case, new bushings and bearings, including new balls for the shaft nut should fix it up. They're not hard to rebuild at all. The shop manual (which you should get) has the entire procedure, including adjusting the shaft bearings and sector engagement. It's best done with the steering gear out of the truck, but could probably be done when installed, but will be a bit harder.
Welcome to Stovebolt.
