If the truck has been sitting 10-15 years with Ethanol gas, it will have water at the bottom of the tank (if it hasn't dried out beforehand). The hard facts are that the alcohol in the fuel will absorb moisture from the air (vented gas cap). After several months, phase separation occurs. The fuel needs to be used (burned in combustion) or drained before this happens. If left unused the separated water will react with steel and cause rust.
Additives can be added, before separation, which binds the water and fuel but this water absorption does not last forever. Then you have even more water in the bottom of the tank.
If you plan on spending significant money on the truck and plan on using Ethanol gas, I would go with a tank made for Ethanol. As a matter of fact I would change everything from the gas cap to carburetor to be Ethanol resistant or Ethanol tolerant. One less thing to worry about.
I decided to only use Non-Ethanol gasoline. I purchased a new Spectra Premium steel gas tank made in Canada.
"Adding CFM to a truck will only help at engine speeds you don't want to use." "I found there was nothing to gain beyond 400 CFM."
