kb-5

how can I update the hubs,wheels,brakes and steering on my kb-5? I'm planning on installing an early powerstroke/c-6 combination as this will be a working medium use truck. Im not all that concerned about the rear end as updating that is straight forward

Based on your stated intended use, I believe a good solid stock rebuild with the addition of a vacuum power booster would suffice.
People tend to deride the stock system, not taking into account the worn condition. New kingpins, tie rod ends and a disassembly of the steering box with replacement bushing and seals and properly adjust toe in should do the trick for steering.
Carful inspection of the brakes, paying close attention to the curvature of the shoe to the drum, smooth bore wheel cylinders, hoses and proper hold down hardware should go along way to correcting the faults. Followed by a correct brake adjustment, including centering the shoes first!
A worthy upgrade would be a late model split master cylinder with a vacuum power booster