#54757, "RE: Drawings and Discoveries by Jose Aurelio Luminary and New Scupper Profile." In response to Reply # 0
You're probably right about the outlet for that scupper on the raised roof.
The lamp you mention appears to be in the same location as that on Olympic. Here's a simple diagram showing its position, with the ship frame numbers indicated, and an Olympic photo showing its relation to nearby features.
I've been looking for photos or video of the Titanic wreck that might show this lamp, but with no success so far. I'd be happy to hear from anyone who knows of any.