Can someone tell me what this is?

Tried posting this in my restoration thread but have gotten no replies, so I'ma see if I can post it here and get some traffic
Was giving my 74 Dart Swinger a run through to get a parts list together and can't identify what this "radiator" looking component is that goes directly in front of the radiator
I assumed it was a trans cooler, but was discouraged on that idea when I tried hooking it back up
The pictures are at the bottom of the first page on my restoration thread, just scroll all the way down
http://www.forabodiesonly.com/mopar/showthread.php?t=304893
Thanks in advance!
-ccsbivens