The sequence starts with a taxi journey (with Honor Blackman) to the front gate. Now, I have no idea what the Castle Peak Road used to look like but in this film it looks narrow and surrounded with bamboo, so I can't say for certain that this was the actual location of the front gate. However, the appearance of the famous red doors seems to be in favour of it being the right place and not some mock up.
But once we are inside there seems to be no doubt about where we are with the familiar decorations and orange/gold-roofed villa.
And lastly the various Chinese archways and structures on the upper terrace and the nice view over to Ma Wan island in the distance before it was ruined by over-development.