Before undertaking any modifications, make sure you have a specific goal in mind. Do you intend to drive long distances at interstate speed, tow trailers, drag race, or do things the truck was not intended to do when it was manufactured? If so, you'll probably need to more or less remanufacture the entire vehicle, and simply drop the antique sheet metal onto a completely new chassis and running gear. A weekend cruiser probably doesn't need anything beyond a careful rehab of the existing steering and suspension system and maybe- - - -or maybe not- - - -a more modern brake system. Even original equipment brakes, restored to "as new" condition, are more than adequate for most, if not all normal driving situations. If "single line" brakes were actually as dangerous and unreliable as some people believe, there wouldn't be any stovebolts left to restore- - - -they would have all been totaled out in catastrophic crashes decades ago.
Before you start butchering up an example of a "survivor" as you describe your new toy, please be sure what you're doing to it will be an actual upgrade, not just blindly following the other lemmings over the cliff.
Jerry