I cannot believe I have to ask this, but how do I replace the rear brake light bulb? My truck came with cheap plastic guards that I believe are OEM, are they covering up the screws on the outside of the lense? They are held on by an adhesive I would need to remove. However on the inside of the lense area towards the tailgate, there is a black plastic cover that I cannot figure how to remove. Is that the access to the bulbs? Seems awful tight on the hinge side. Oddly my Isuzu manual shows nothing on replacing bulbs.