Hi Adam,
you can only *access* the hardpoints that are on the ship's display. you can use the other hardpoints for defense only weapons like adds, plaD, and phasers that you'll only use for point defense. Shift Z *might* also fire weapons that are on HPs that don't show on your ship's display. I'm not certain, I haven't actually tried that. You might be able to overload weapons in HPs you can't directly access by selecting R on your keyboard then selecting overload on your weapons panel. Sorry if this isn't the answer that you were looking for. I hope it helps some.