In the days when the Advance Design pickups were new, these trucks were bought for work, often on the farm. A very common accessory/modification would be stake and rail sides to allow the hauling of much higher loads than would be accommodated by the pickup bed itself. Bill Green of Canton Ohio e-mailed me a description and pictures of the stake sides on his Grandpa's '52. Here is what Bill had to say...
Here is some of the information on the stake rails that my grandpa got on his '52. As far as I know, he purchased the truck with the rails. They are painted the same color and appear to be made to pattern, not home-made, fasteners all consistently placed, fit and finish uniform, etc. They appear to be made of pine; possibly yellow pine.
The only problem with reproducing them may be in coming by the hardware that joins the rail sides at the upper corners. They appear to be similar to a fence gate latch. They are heavy in gauge and are identical pieces for each mating pair. They appear to be made from a piece of flat stock, cut to rectangle for the mount plate, and the latch piece welded in from one of two locations to make the mating of the two match at the corner. The other fasteners are just carriage bolts fastened with washers and square nuts.
You can see from the pictures that the extra length on the front and rear uprights is left on the bottom. On the front, this provides a positive placement against the front bed sheet metal. On the rear rail, this allows the tailgate to lock the rail in place when closed.