what year truck?
You will find some screws on the face of the panel and accessories.
the power locks and windows simply clip into place.
once you have all that done you can use a long flat head screwdriver, or metal ruler, or something flat and firm to get between the door panel and metal door (around the edges)
The panel is held to the door with plastic "christmas tree" clips, they press into holes in the metal door. If you are careful you will be able to re-use them and put the panel back on with out problems, they are spaced around 3 edges of the door about every 6-8"
Once you have it all loose the panel pulls up and out of the door, over the lock button. it helps if the window is down for this.
Good luck, hope that helps.