How do you replace the third brake light

How do you get in to where the light is? It is all enclosed.

How do you get into the tailgate to change the light?

Open the tailgate at the top in each corner are two 10mm bolts remove these. next gently pull the plastic cover until its loose start on the right hand side working up and across the hatch notice the wiper washer rubber tube, you will not be able to completely remove the plastic cover just gain access to the light harness top of hatch. NEXT notice the 4 holes at the top remove two more 10mm nuts and undo the two plastic tabs squeeze them with long nose pliers, press forward so they are released, lower the hatch / tailgate and pull back on the "spoiler" you can now remove the two screws holding the light in place... replace with the new light and reassemble all the fasteners... first time expect to spend 30 minutes to complete this change go slow. Regards