I went to my local metal supply today to find a piece of 16ga to fit my tailgate since I used all I had on the floor. The last couple weeks when I have checked the remnant section all they have had has been thin gauge like 20-22ga but today they had a couple pieces that were big enough to leave me some extra metal. So I walked out of there with the piece of sheetmetal that I needed and with $5.11 less in my pocket!
I cut it to size, primed the tailgate and the new metal edge, clamped it in place to get ready to weld it.