I worked there for about 3 days a few years back when those straight line winds blew the side off the Gibson factory and twisted one of the construction cranes building the FedEx Forum around to the north, forcing Clear Channel on Beale's traffic, production, management and salesfolk to ride shank's mare over to Union until the crane was locked down. WREC and WEGR operated in the hallway of the bottom floor of WPTY on Union Extended and KWAM simply simulcast WREC during the period.
The main things I noticed in that brief experience were:
1. The Smithsonian called three times asking when they could come get that danged elevator!
2. The office pool among the regulars (WDIA/WHAL/WHRK/KJMS) was giving odds on how many Beale St. people would trip going up or down those wicked steps into the production studios and control rooms.
3. I never did find a restroom.
Jackie Crenshaw, a great lady and CCR's executive secretary, was once the Plough record librarian on the 2nd floor. I heard tales from her about the size and completeness of that fabled Plough library and always wished I could have seen it in its glory.
If I hadn't worked first at WREC in the basement of the Peabody, I would have been claustrophobic in the Union facility!
BTW, Hoyt Wooten's office in the basement extended out under 3rd Street and had WINDOWS!. There were two windows on the west wall with blinds, curtains and backlighted so you had the sensation of light streaming through 12 feet of river bluff. It was the sort of thing God would have done if...
Good luck with the condos. What tales those walls could tell!!!