Here's the photo, with caption:
http://www.flickr.com/photos/tennken943 ... pool-metra
Said caption reads: "Sitting at the back shop at NRE in Dixmoor is the cab of an unknown F40PH donor. Although the engines are being rebuilt at Progressive in Mayfield, Ky. New cabs and fuel tanks are built here and trucked down south."
What is probably going on here is the cabs are being pulled off the locomotive, shipped to NRE Dixmoor, modified/upgraded, and then sent back to Progress Rail. It's possible that cab won't get put back on the locomotive it came from, which might explain why the ex-Amtrak #216 came back with standard-issue Metra marker and ditch lights - maybe that's a Metra nose on that unit.