That looks like the Tent, Marquee, Universal, Hospital, Extending 8340-99-942-4586 that is the postwar version. If you are a WW2 group do you have the earlier version JA 2080 with very few "windows"? I wonder do you have the extensions?
Well it should talk 12 men an hour to put up. I have the wartime instructions I can scan in due course.