I just recently cleaned my tank out. First took it to a machine shop to get hot tanked. then putt a couple feet of chain on the inside and some water and shook it out until there were no more rust particles and the water was clear. Let it dry over night inside. Then rinsed it out again with Mineral spirits. Then I used the gas tank sealer that is for sale on Classicparts.com. Worked great! Now the inside of the tank is new and I put a couple coats of paint on it and it looks brand new! Hope this helps