I second Charlie's advice, but do not start checking your brake system at the rear wheels. Start at the front where the hub and drum assemblies are easy to remove and replace. Pull them off one at a time and study what you see against what is shown in the illustration above and that in your service bulletins. Disconnect the brake rod where it attaches to the operating arm behind the brake backing plates and move it back and forth so that you see how the brakes operate and how the various parts relate to one another.
After you are confident that you understand how the brakes function, check the linings for both wear and contamination from grease or oil. Check also to see if the wearing surface on the inside of the brake drums is scored or pitted. If the linings are contaminated or worn down so that the rivet heads are no longer completely below the outer surface they need to be replaced. If they drums are scored or pitted, they should be turned down to a smooth surface (this has to be be done by someone who knows what they are doing as there is limit as to how far the drums can be turned down before they need to be replaced.) Check everything else exposed and attached to the brake backing plate for excessive wear as mechanical brakes can be good brakes, but only if all of the components are free of excessive wear. Now do the same thing for the other front wheel and only then tackle the rear wheels as removing the hubs can be a challenge as Charlie is suggesting.
Once you have checked out all four wheels, check for wear in the clevis pins (one on each end of each brake rod) and in the holes in which each clevis pin is inserted. Check for play in the brake cross shaft assembly on the center cross member (where all four brake rods attach). Wear in the cross shaft bushings is a common occurrence and its presence means that you will never get all four brakes working with the same effort until that wear is eliminated by replacing those bushings (there are better substitutes available today for the bushing material that Ford used originally).
Check for wear on all of clevis pins and their holes in the various arms on the cross shaft and on the rods to the brake pedal and hand brake. Replace any and all that are worn excessively. If the holes in the arms are worn excessively, they can be welded up and re-drilled to their original diameter or if only slightly worn drilled oversize to be used with new over-sized clevis pins (personally, I recommend the former and not the latter cure for wear).
That's enough of a to-do list to start with.
