Don't know what PSFS stood for, but since the letters are a texture on the model can't light them up, they will just have to remain like they are.
Most likely the windows on the left and the right side would have opened, don't know why they designed the building like that in the 30's though.
By the way, here's the photo of the original prototype building.
PSFS Building.jpg
And compared to my 3d model that's still a Work In Progress
PSFS Building Progress 1 A.jpg
PSFS Building Progress 1 B.jpg
PSFS Building Progress 1 C.jpg
About the building.
The PSFS building was completed in 1932 and received immediate recognition as a breakthrough architectural achievement. Touted as the most modern building of its time, it was the first building of its size to be fully air-conditioned year-round. Expensive materials were used throughout the building. Most of the furniture and design elements were custom designed as there was no inventory of such modern furnishing in the US.
The name of the building was Philadelphia Saving Fund Society, that was what the PSFS sign at the top stood for.
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