hi GradyB
a new tank might be nice, but i appreciate and support your desire to fix the one you have.
Warning - always purge your gas tank before attempting to blow yourself up, what i am recommending could be dangerous if not executed properly.
according to JBWeld documentation,
if applied on clean metal without oil or gas the fully cured epoxy is rated for full gasoline contact, including modern fuel and oils.
however, even a trace of motor oil will keep it from curing proper, i have experienced this phenomena first hand, i would expect most components of gasoline would have the same undesired affect to the curing process. i suggest you bake out all the oils and gas at the local spot before applying the epoxy,
using a propane torch would likely be sufficient, scrub the surface clean after you cook it good.
heat should also allow you to bake off all the old epoxy without so much effort, it will turn to ash before the steel deforms.
but...
if it was me, since it's off the truck, i would go for the acetylene torch and braze a new steel patch in place.
I love JBweld, but if i can put metal on it that's the way to go.
-s
