Don't have much to add to this except some pics of my 30 year old tanks in a 1987 Grand Banks 42. I bought it without inspecting the insides of the tanks and was nervous beyond belief when I had them opened and inspected while getting the bottom painted after purchase. There is some slight surface rust but I think they are about as good as 31 year old tanks can be. Got a clean bill of health from the tank guy. He removed some gunk but not too much and made new gaskets for the inspection ports. I have a ton of old documents on repairs, upgrades, maintenance but can find no record of any prior cleaning or even polishing. Just putting these up so you know it is possible to have oldies but goodies.