Used some “Permatex Fuel Tank Repair 84334”. Its an epoxy stick. Cut some off, mix, press into place. Let it cure. Looks a bit like chewing gum under a table.
Working well at this point.
The leak was a very small hole on an old crease from bottoming out at some point in the distant past.
The interior of the tank is rust free. There is an old patch in what looks like JB Weld at the other end of the crease that is leak free.