The tank looked very clean after they cleaned it. It had some black areas where I assumed the acid neutralized the rust. I did notice yesterday when I siphoned the gas out of the tank that the filler neck has rust scale. I guess they could'nt clean it because of the plastic flap by the gas cap. I plan on taking the tank back to the shop and have them clean it once more, and this time have them coat the inside with sealer. What I'm curious about is if anyone out in this forum has ever had their tank coated with good/bad results.