Actually, that looks like Rutherford Ave, looking south. The bridge behind the elevated would be the since-demolished connection from Rutherford Ave to Mystic Ave. And I think the second car from the left is 01000, which is up at Seashore.
"The destination of this train is [BEEP BEEP]" -announcement on an Ashmont train.
This is approximately where the Market Street bridge over the mass Pike is today. The first cross street on the right is Lincoln St, I believe, and the tallest building visible beyond that is Roddy Hall, which is the only thing in this photo which still exists.
A number of station rebuilds in the last few years have uncovered mosaics that were simply painted or plastered over rather than outright removed. Scollay Under, Arlington, Broadway, Central, and South Station all have preserved mosaics (and I don't know how many of those were known before the rebuilds). Hynes also has several covered mosaics that will almost certainly get restored in the pending renovation.
So there's a small but non-zero chance that one of those Symphony mosaics will show up during rebuild. After all, just last year we rediscovered a pair of staircases to the station that had been forgotten since 1974.
"Give me an unobstructed right-of-way and I'll show them how to move the earth!"