One of the many street side scenes from the film includes this nice shot of Pottinger Street - famous for its steep stone slab steps. This part of it leading south from Queen's Road has been used many times over the years for film and TV.
Now, I don't get much chance to head into Central these days, but it's possible that Redge House (you can just see the "R" of the name next to the Queen's Rd Central street sign) has recently been demolished [Edit: yes it has, see Thomas' comments below]. It's still visible in Streetview for the time being because the Google stuff was recorded back in 2011. It's a big shame because it was quite a nicely designed building and was fairly new when this film was made (it was built in 1971). Anyway, here is the Streetview of the same location.