Look under member projects, then lighting, it will say reverse light bulb replacement. I know you want to replace the tailight bulb, but this will get you to all the tailight bulbs.
Drop the tailgate, on each side there's rubber plugs, remove them and there are two screws, remove the screws (sorry can't remember what size, maybe 7-8mm ) you'll see the pigtails for the taillights, twist and pull out, pull out light bulb and reverse the order.
Dave, just to make sure you don't have the dreaded common issue of the TIGHT wire harness in the column causing the problem, tilt you wheel in the other direction and see if it works.
If so, also under the PROJECTS section you will find details about this issue..
