Any welding, modification, replacement, reinforcement, painting or other work on the fuel tank or filler neck should be done by a qualified person with understanding of this regretfully necessary and rather hazardous job since even after extensive cleaning and flushing of the fuel system, explosive vapors may remain and may be ignited during the work. Should the fuel tank be removed from the car it should not be stored near inflammable materials such as sparks or flames with added caution when storing the tank in a garage containing natural Gas type appliances, sparks from the pilot light may cause explosive reactions.