1934 Ford Cabriolet gas tank issue

[Tim ford]

I have a 1934 Ford Cabriolet rumble seat coupe. A friend recommended putting Sea Foam Engine Treatment into the gas tank to run better. Few weeks later the engine stopped running and I discovered Sea Foam reacted with the paint in the gas tank (ethanol never bothered the paint) Seems now I have to remove the tank and have it cleaned out. Trying to get an idea how big a project this will be. I’m 75 years old and the eyes aren’t what they used to be!
Thanks.