If I am not mistaken, the gear box in your truck has a one piece steering column. Meaning, the steering shaft is part of the gear box. You would need to cut the shaft off and make it into a double "D" shaft and use some sort of coupler joint to mate up to the modern column.
My truck has manual disk brakes, it will stop just fine with enough pedal input. If you are getting older and have weak joints or sore knees, then power brakes would be the way to go. I went to disk brakes just so the front and rear bolt patterns would match and I could run 5 lug wheels. I suspect drums up front would have done just as good of a job with less pedal pressure.
I also have manual steering, I used a gear box from a 1941 truck ( mine is a 1937 ). The '41 has slower gear ratio and better internal design. I could tell right off the ratio was different, much easier to steer. It still takes some effort when moving very slow, but I so no reason to add power assist. Tire air pressure makes a huge difference on how easy it steers along with tire width. I run a 205/75R15 at 40 psi, when it sets for a while or gets cold and the pressure drops, it shows in the turning effort. I would never consider power assist to this steering set up, the ratio is way to quick, in fact it's a little spooky making quick turns now. The power steering gear box would need a much slower ratio or a smaller diameter steering wheel would be needed.
