Wow, very cool.
Looking at the address on the scans it says that The Rover Motor Company of North America was located at 10889 Wilshire Blvd, LA 90024. That's about three blocks from my apartment in Westwood. There's a highrise building and an large art museum at that site now. Because there's no suite number listed on the ad, I'm guessing it was a small office building at the time. Just thought it was interesting that the old LRNA was so close to my home (many years before I was born in '77)...hope I didn't bore ya!