Sunset - Paul Chin Pei (1971) - So Kon Po Stadium, Happy Valley

The location of the two lovers first official rendezvous looks as though it may have been held at the previous incarnation of what is now known as HK Stadium i.e. the location where the Rugby 7's is held every year. Back in the early 70's it was still a concrete monstrosity.

In case you didn't realise that this is what the So Kon Po stadium used to look like there is a good clue in the second screencap which shows the external wall of the neighbouring South China Athletic Association sports ground along Caroline Hill Road. The small building behind Paul Chin Pei's head is the Indian Recreation Clubhouse. He's standing in the east side stands.