Alright, I think I see what the problem is. The wheels are indeed for a later model truck, '88 or newer. I somewhat suspected that would be the case being a 17" wheel, as most of the 6 lug wheels available for the older trucks are 15".
The steering box/pitman arm/steering arm relationship looks pretty good. I don't think the truck has been lifted, the '60-'66 4x4s sat fairly high to begin with. The axle is definitly from a later truck, most likely a '78-'87, as it appears to be the 10 bolt with open knuckles.
Looks like the fix will be different wheels. Look for wheels with no more than a 3 1/2" backspace. If they ask for an application, use the '73-'87 K10 or K5 Blazer as the fitment.
