I worked for a time in the old GM building on West Grand Blvd. I had a office on the 13th floor. Nice place to work, just needed a technology upgrade and some other improvements. Not too hard of a place to park.
Then worked some at the RenCen. Interesting place to work with nice views of Detroit, the river, and Windsor, Ca.
I ended up retiring from GM while working in Warren at Engineering at the Tech Center. Easiest place to get to and get around. It was a good place to work from a commuting location and campus.