The white columns with red writing along the left side of the street tie up with a picture Arthur found at the following thread on the Uwants forum (it's a great resource for old Hong Kong pictures as long as you have a decent grasp of Chinese literacy (sadly, I don't).
So we now know that this particular stretch of road, where the (most likely) fictitious "Celestial Empire Hotel" is situated. This whole stretch - between Jordan Road and Nanking Street - has been redeveloped, however, the curved corner building in the mid distance is still around and it's on the corner on Nanking Street and now houses the Goodrich Hotel. It was built in 1964 so must have been brand new when this film was shot (probably why it looks so clean!).
Anyway, once again a massive thanks to Arthur for finding the proverbial needle in the haystack.