The Mercury-Redstone booster for flight Mercury-Redstone 4 (MR-4) is here being erected on the launch pad.  Photo published on July 16, 1961, but probably taken much earlier, since the booster was normally erected weeks before the launch date.
NASA
Kennedy Space Center Photo Archive, <a rel="nofollow" class="external free" href="http://science.ksc.nasa.gov/gallery/photos/1961/captions/61-MR4-45.html">http://science.ksc.nasa.gov/gallery/photos/1961/captions/61-MR4-45.html</a>