I can't offer much info on the original steering box,but if you decide to replace it,you might look into a newer box. On my '66 C-60 I used a power steering box from a 1974 C-60. It bolted right up. Be sure to get the hoses,ram,pump,reservoir,and all related brackets from the donor truck.The only problem I ran into was the rod from the spindle to the steering box was an inch and change too long,but that is easy enough to remedy.I didn't mess with it. It drives fine.It just means the truck will turn sharper one way than the other,but both directions are better than original. Besides,you'll probably set the steering stops anyway.You might want to center the steering wheel too,so your turn signals will cancel right. Also,if you want to use the power steering,you'd need to build a bracket to fit the middle of the axle to attach the end of the steering ram to.It's pretty easy to make a block that fits the contour of the axle with a proper sized hole through it for the rod end on the ram to connect to,and use a couple of spring u-bolts to attach it to the axle so as to not weaken it by welding on it.It's definitely worth the swap!
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