which Sea Foam product should I use to clean up the gas tank? [SOLVED]

Thanks for the question, Alex!

I’d use Sea Foam Motor Treatment (red and white can) or High Mileage (black and silver can). Both are made to clean fuel residues and deposits. High Mileage is formulated as a strong cleaner for higher-mileage vehicles with years of stubborn buildup/deposits. Either one would work!