Skids
I had a similar problem with my Harley. I called a custom paint shop for bikes, and asked who they sent their tanks out to for cleaning and sealing. The guys they sent me to, preserved the high dollar paint job, and coated both tanks, he wouldn't give me a gaurentee because the couldn't do their usual cleaning process and preserve my paint job. It was 4 years ago, still working great. A few tips, don't leave the tank half full when you park it for a while. Chevron gas is high in Mtbe here in CA. That stuff eats liners, but as long as the tank is pretty full, less air space for moisture and oxidation to eat the liner.