Here’s what I did to mine. After grinding the roof gutter cavity to bare metal and coating with epoxy primer, the lower portion of the rain gutters were filled up with Evercoat Maxim self leveling seam sealer. One huge advantage to this product is that it uses a standard caulking gun. Now instead of water sitting in a trough with no drain, it just flows over the edge preventing future rust damage. These are the best photos I have to offer:
