I been using white vinegar this spring and I'm pretty satisfied with the results so far. I'll post another method below, one I have yet to try. Your input is welcome.
With electricity.
Great thread.I've done (still doing it) the molasses trick, posted it years ago. http://www.forbbodiesonly.com/moparforum/threads/rust-removal-by-using-molasses.36965/
I swear by this stuff too, works great, but it's just water down molasses.EvapoRust for me.