In this shot of Tunnel 4 Malcolm is standing by the entrance to this section.
If you went through the door where Malcolm was standing you would enter this corridor.
The offices on your right - in order - Jig and Tool Records, Secretary, Chief Planning Engineer.
This is the same bit but looking back towards Tunnel 4.
This sign indicates the passage to: Plant Drawing Office, Technical Records, Jig and Tool Drawing Office and Hollerith.
Confession! - I'm not 100% sure where this was. I think
that It is inside the previously seen offices looking north.
Cross passage running west - east through the office area.
Moving along to the next access point from Tunnel 4 we are looking into what was The Dark Room in the 1940's. The second room was the Print Room.
Moving through the Print Room we enter the Plant Drawing Office. The cross passage seen earlier runs across between this and the next room.
After crossing the cross passage(!) we are in the Jig and Tool Drawing Office looking towards the Hollerith Office.