"Fixture" on CNW/CMO AAR Recommended Practice Gondolas

Jim Gerstley Collection

Yesterday, I posted a question to the Steam Era Freight Cars list (STMFC) on Yahoo! Groups in the hopes that someone could identify a detail on the CNW/CMO AAR Recommended Practice Gondolas built between 1945 and 1956. Here is the query:

If one looks at photos of the CNW/CMO AAR recommended practice and related "11-panel" gondolas of 1945-1956, there is a distinctive detail at the lower right corner of the far left panel (adjacent to the left end). It appears to be a casting of some sort. In looking at my photos, I cannot identify it or its purpose. Since it is on both sides of the car, it is unlikely a defect card holder, as these were usually only on one side of the car. Does anyone know what this detail is? 

It can be seen in the articles on these cars by Jeff Koeller in Mainline Modeler, May and June, 2005. 

The Sunshine kits do not duplicate this feature.

Page 42 from May 2005 Mainline Modeler

I received a few requests for photos or at least to be pointed to photos. To that end, I have created this blog post. Click on any of these images to view a larger version. The two-part article by Jeff Koeller is excellent and I recommend adding it to your library if you do not already have it.

Detail of CMO 88173 from page 42 of May 2005 MM.

CMO 88173 has its defect card holder (a different type of defect card holder) mounted in the same location as CNW 70351 shown above.

Can anyone identify this detail? It almost looks like one of those beer bottle openers mounted to the face of a bar... just sayin'