The bridge was definitely there and I personally walked across it numerous times. As a university student around 1975 I has a part-time job at the Simpsons-Sears warehouse for the Christmas season. Known then as the Mail Order Building (MOB) the warehouse was part of the catalog shopping operation which was still huge. I was part of the crew that unloaded tractor trailers (loading docks on west side of bldg) and ran the goods up to the various floors on large freight elevators. Catalog orders would be picked and packed on the upper floors. On our break we would cross over the bridge to the cafeteria in the office building (the inverted pyramid). Funny to think that where I used to drop skids of Christmas toys is someone's apartment now.