Re-colorized and improved five years since original creation. It has been pointed out to me that this ambulance would not ordinarily be found on LaSalle Street, in front of the Icarus and Daedalus mosaic. Artistic license.
A print of the piece is going to hang on the wall of Firestation No. 98, part of the Water Tower District, where Ambulance 11 lives. A very cool Google Sketch-up Model of the firestation can be found here.