My upper tailgate was in fair shape. It had some small dents, inside and out. I used a welded stud puller to remove the dents. There were also five small cracks around the support strut bolt holes. I welded up the cracks, dressed them with a flap wheel, and fabricated a 16 ga. reinforcement plate. The tailgate was chemically treated for surface rust; sanded and primed. The primer was block sanded to reveal any imperfections (multiple times). Then the color coat was applied inside and out.
I generally use postimage for this forum, but I also have another online photo album, with hundreds of photos of this build. I have provided the above link for anyone who wants to check out the progress, and probably waste an hour of time….