'97 Explorer Power Control Box
 

How do I replace the Power Control Box on a '97 Explorer.

Box is located in engine compartment above the drivers side wheel well.

Apparently there is a short from the fuel pump relay in the box.

If your asking about the power distribution box, or fuse box, under the hood, the only way to replace it that I know of is to replace the underhood harnass. Not even sure you can still get one for a 97 model Explorer, but if you can, be prepared to pay 3-4 hundred dollars for it.
The better idea is to repair the harnasss that is damaged, unless it is the internal plates in the fuse box that are shorted together. These are put together like a jigsaw puzzle.