Hello Mr Reid
The building my beeter half worked in was 5 or 6 stories high so it really stood out on the airport especially as it was not that far from the southern runway but obviously all legal etc. I was an onlong office block with relatively small windows and if you recall where the original BEA Engineering base hangars were it was sort of grafted on to the eastern end of the second row of those hangars . . I have tried to find a link to a suitable pic without success although if you Google images for BEA hangars there is a picture of a Vanguard with the Bea base in the background which clearly shows the office block. I have a feeling it is gone now-my wife moaning about her past being eradicated.
For someone like me who grew up literally next door to LHR and who remembers -not clearly admittedly the extension of the southern runway , the Beacon, and the changes to the terminals its sad but of course they were necessary , a background to my life for many years watching it change as i grew up and being a very regular user as a grown up lol. I can hardly think of anything left from that era other than some of the hangars under discussion altho the old MT base on the north side by the Bath road , may still be there actually, must be one of the few original buildings along with some of the huts and prefabs just to the north of the BA ( BOAC ) base