Need to clean out a gas tank on my '64 Triumph Spitfire and I read in a spitfire forum that filling the tank with cheap white vinegar and letting it set for about 48 hours would clean out the rust. Never used this. Wondering if any one has used this with success. It's a 10 gallon tank and H.E.B. sells it for $1.65 per gallon. So price doesn't sound unreasonable if it works. Thanks for your help. Joe.