If the body is in good shape, go through the brake system and get them in reliable working order, then tinker with the engine to get it running, then I'd say drive it a little while like it is and see what you think of it. You may actually like it as is. You can change out frames, suspension, drivetrain, etc, it's all a matter of what you want from the truck. Do you want an original or close to original truck to drive around, or do you want a hot rod. It will be fun to drive and safe just the way it is.
Being a stock 1 ton, it will be a slow vehicle. You can change out the rear gears or axle for a little better cruising speeds if you'd like. You can change the suspension, but then you will be losing that old truck feel just my opinion. Post some pics when you get the chance!
I know there is another feller on here somewheres that put a bed and widened fenders on a dually and I think it looks real sharp.
