Brooklyn

On Monday, blogger 423 Smith posted this photo showing what Smith Street looked like in its pre-Restaurant Row splendor. Back in 1930, when this photo was taken, there was a grocery/soda fountain spot on the ground floor of Number 423; meanwhile, the blog points out, the elevated subway was in the process of being built. Does anyone know what year it was completed?
423 Smith Circa 1930 [423 Smith]