I have thought about taking my side panel to a machine shop to have this done to it. I would tack in some black wire mesh where the eye cut out is. The guy told me it would be about $75 to set it up and cut it if I brought in a photo ready to go.
That's a pretty good price. What shop? A couple of people have asked me to do mods like this, so it would be good to be able to direct them somewhere.
I've seen people use a dremel for cutouts (not quite so sophisticated), and they came out fantastic. I have no idea how they managed it. I don't have the patience, nor would I want my neighbors to endure the sound of cutoff wheels on metal for hours and hours.