In 1955 all of Grand Circus Park was torn up to put the underground garage into. So that "tree-less" W. GCP pic that Dexlin posted likely dates to between 1956-59. In 1959 the David Whitney Building got its' modernization [[which has mercifully been undone a few years ago), and I believe that the Michigan Mutual Building [[formerly Stroh's HQ) was modernized around the same time, since it still shows its' corner towers.
Here is the 1955 "big dig" of GCP...
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