I want to build a custom water/meth tank for the hatch area of my tib behind the seat. There would be a 2.5" filler cap on the top. So far the design will net about a 6-7gal tank. My concerns would be the effects of methanol on aluminum. Will it corrode through? Can I use gas tank epoxy sealer to coat the inner side of the aluminum to protect it? The exterior probably will be powder coated when all done. Thoughts/Concerns?