Natural aluminum has galvanic reactions very often. There are a bunch of substances that react negatively too it. It's a big list.
I can say that my car, 4066, has the painted steel tank had no signs of it ever being wrapped in anything. It only had some kind of a fabric soaked in some type of an asphalt that was put between the tank and the support underneath it.
I think that it might not be possible to give the tank a long term repair. Whatever you do now is a temporary thing.
The tank to install is the stainless one that Hall has. It isn't cheap but the steel service part is actually a hundred dollars more.
At least with stainless there won't be any kind of a corrosion issue to be concerned about in the future?
Is Zonkey a very early car or a euro version?
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