We have an 85 W-250 truck, and the steering box does look like a GM style gearbox. The steering column looks kind of like a GM too, it is also a factory tilt column, and it does need a new turn signal switch harness, which are about as rare as hens teeth. Some people have mentioned that a factory GM signal harness may work, but don't know. I would look at different style pitman arms, other than Chrysler, because I'm almost certain, a lot of the pitman arm splines, are the same for many applications. A small story.... my Father used to build hot rods, street rods, and a few custom's, and he was building a 48 Plymouth Deluxe 5 window coupe, and he used the original front suspension (was converted to disc) and he used the stock 48 ply pitman arm, and the arm slid right on a 70 Nova manual steering box, no problem, car drove like new, when done.
