Good advice so far, any of those will work. I'll just add that I've personally had the best results with Evapo-rust. Very effective, safe on rubber/plastic, no flash rusting, and a little less hassle than my attempts with vinegar. It's not quite vinegar cheap... but it's close, and most auto/hardware stores, and even Wal Mart, seem to carry it. When you're done just pour it back into the container and save it for next time.
As Mighty Gryphon said, avoid messing with the fuel level sender if you can, and be careful with it if for some reason you do take it apart. Not only the arm, but if you twist/crack the wiring cap there's a good chance you'll find a puddle of gas under the bike, and/or soaking the ECU/battery the next day. Plus the gasket "must be replaced" every time you open it... Don't ask me how I learned all this.
And sure... on the one hand, gas fumes and vacuums don't go well together, "allegedly"... but on the other hand, they do say these bikes are bomb-proof... :2thumbup: