74 power wagon dream truck...

As for your steering box, Straight Line Steering here in California can set you up with a very nice box. They are a small shop, that do excellent quality work and only use US made parts. Not your standard rebuilt steering box from the parts store.

Their website is kinda behind the times, but check them out. Give them a call. I have their box on my ‘74 W200. And one on a ‘73 Ford F-350.
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That is good to know of extra sources, we have Steer-n-gear in OH which also does excellent rebuilds.
I have one of their boxes on my Duster.

I need to change the box on my 47 / 74 truck, the box just developed a huge gusher leak where the plate bolts on the adjuster nut.
I am robbing the box of my 75 parts truck. I will chance a used box because I already have it.