I had a gas tank in my 73T with a very small leak at the front seam. I tried having it fixed at a local radiator shop cheap. It came back and after a few hours starting leaking again. I then had a body shop who was replacing the front pan for me look at the tank as well to see if it was repairable. They said it wasn't repairable. I replaced it with a new tank.
I brought the old tank home and had it sitting on my rear balcony for a month under a few plastic bags. Finally I decided to have a look at it myself. I filled it with water and watched for the leak. After a few minutes I found the leak was coming from 3 very small pin sized holes. I got out the metal bristled sander bit and sanded all of the undercoating and surface rust away. I put some JB liquid weld on it and refilled it with water. No more leak. So now that the tank has water and most likley surface rust in it, what can I do and/or buy to clean the tank out myself in my garage rather than send it away to a local shop? Is there an off the shelf product that I can buy to do it with?
Any suggestions appreciated.