Interesting ad glass, I would not hesitate to remove the decals, if I owned the glass... But, I would try every trick I could think of, to save the decals. (do you know if they are they vinyl or water transfers?.. Also I would place them between some plexi if I could maintain the decals...)

I will need to check some of my images, as off the top of my head... I don't remember seeing such designs (under the decals) before...

But, maybe they were quite abundant in the Northeast during the mid-30s?

Looking for Tide Water/ Tide Water-Associated/ Tidewater items