HI,

I am a proponent of the sucking method as long as it's someone else doing the sucking, it's always a whole lot funnier when the gas is squirting out of someone else's nose.

My technique.

Good length of hose:
Push hose into tank.
Cover hose with thumb
Pull hose out
Quickly release thumb while pushing hose quickly back into tank
Then quickly reaply thumb.
After a couple of times you'll see the fuel in the hose and then let gravity take over.

I empty my neighbor's tank uhm I mean my fish tank this way all the time.

Good luck,
PS> I wouldn't smoke during any of the operations mentioned, car and or you could go boom.