Old gas

My dart sat in the garage in so cal near the ocean for 4 years with a 1/2 tank of standard fuel (with ethanol)

I filled the tank the rest of the way and drove it till it was almost empty.

Filled it again and did the same thing.

Then I rebuilt the carb and changed the fuel filter.

No issues.

And the tank was clean as a whistle , the intank filter was clear, brown but unobstructed.

The worst part of the tank is about 5 dime sized rust spots on the inside. Well that and the slightly crushed spot!