Sounds odd, but with what you described, fuel pump failure sounds like what is happening. Fords can be fickle on setting codes. Misfire codes wont always set, unless you can get the vehicle up to hwy speeds, etc. With a fuel pump problem, it won't often throw a code at all. Just have to use a fuel pressure gauge to check. As others said, unless your bed is full of junk, just undo the filler neck, pull your tailgate, and undo the bolts. Either til the bed, or disconnect the electrical connector(s) by the tailgate, underneath, and remove the bed entirely. Two men can easily pick it up.