Sorry...a bit late to this, but just joined this site recently and I see a point (important in my opinion) that hasn't been mentioned. With the 1958, you could have had 15" or 16" wheels/tires when the truck was originally built and I think you need to know that. The front axle would have been different depending on wheel size. Any front end shop can tell you by checking one measurement where your scrub radius is and from that they should be able to know if you need 15 inch or 16 inch wheels for your axle. If they try to minimize the importance of the scrub point, please go find a different front end shop. If your truck came originally with 15" wheels/tires (the most common for that year as 16 inch was a buyer option), changing to 16" will have an effect on your steering geometry. Basically you will change your scrub point and that can make your truck feel unstable, wander and act oddly while braking. It may even make your truck more sensitive to road crown. And since the straight axle allows for no camber adjustment, you can't correct it. You get a wee bit of leeway in the factors, but you don't get a lot and once you've passed that acceptable point, your truck will start feeling like a shopping cart with one bad wheel. On vehicles without power steering and with straight axles it is a lot more noticeable because of the reduced caster angle (to make steering easier). It is a fine balance but when correct these trucks drive very well. Good luck!
