Along with the vinegar and water, you might try using old newspaper to wipe it away with, something about the printers ink and the vinegar. Also is pretty much streak free.
I'm with this guy! Not sure about the WD40 though!
1950 Chevy Advance Design 3100 in Scotland In the Stovebolt Gallery More pix on Flickr. I've definately got this truck thing in my blood ... my DNA sequence has torque settings "Of all the small nations of this earth,perhaps only the ancient Greeks surpass the Scots in their contribution to mankind" Winston Churchill.
Not sure about the WD40 though! 
