Not sure if any of you have seen this... The beginning of this video shows some of the construction for the Hemisfair in 1968 including the Tower Of the Americas, Lila Cockeral Theater, Placeo del Rio (now the Hilton) and the old Hemisphere Arena. It also has few skyline shots from before construction.
Looks like SA had a monorail back in 1968! (Albeit a cheap one)
http://www.youtube.com/watch?v=sYP8oSp2WTQ