Definately run the fuel as low as you can before doing this. If you have a couple of 5 gallon gas cans (the red plastic kind), what worked for me before I got a new tank with the drain plug, was to drain it using the rubber hose that is connected between the sending unit and the hard line. Leave it attached on the sending unit side, loosen the clamp on the hard fuel line side, slide it off the hard line and point the rubber hose into the gas can, keep an eye on it and if you have more than 5 gallons you can tighten the clamp back up to stop the flow, grab another can and repeat. Somehow I always end up taking a fuel bath anyway but this kept it to a minimum.