Looks great! I would Like something like this for my machine. Would be tough to do under the plastic, as the tint in the window would make everything muted and difficult to see. I agree that having all the faces pointing in (or out) would give the art a little better flow. RidicRick at Arcade Skin does a lot of design/printing for pinballs, and has access to an SF2 machine (He did a custom overlay I am getting for my apron).
Contact him through his website, or he is also on facebook (Arcade Skin). Good guy, and if you supplied the artwork, I'm sure he could help you out pretty quickly.
Keep me posted on this, I would love to see the finished product!