Checked the building out you've got posted at 1717 Olive St. Looks like its the Butler Brother's Building.
The sign with the cup says "Christian Board Pub." But not sure what Pub. stands for exactly. Also mentioned shipping and receiving.
Most interesting takeaway for me is that it lines up with the Apotheosis Statue…
I don't know if you've come across this yet, but there is a part of town just north of Washington University and Forest Park called "The Loop."
I believe Jack Dorsey (Twitter and Square creator) is from there. There is also a MOONRISE Hotel there. Chuck Berry was from there.
There is also a Scientology building there housed in an old Masonic Temple. They didn't even bother to take down the mason symbols on the outside! Interesting, isn't it? Lots and lots of mason activity in St. Louis.
Have you found the Des Peres tunnels yet? I saw someone in this thread mentioned Underground Ozarks. Whoever did is a hell of a researcher.
You should look at where the tunnel runs. Wonder if there are branch offs of the tunnel…