When the new 3HW model was announced to the press, this is one of the photos they used this one from MOTORCYCLING,the canal back ground suggests that it was taken near the temporary factory before meriden opened. 
The man with the pipe could be one of the triumph gaffers,the wartime weeklies used a low grade paper after 1941 and the photos are very poor on it,here is another photo inside the Warwick factory. 
Yes, both the 350 3SW and the 500 5SW were built at Warwick for the WD...
Here's a 5SW I rebuilt a few years ago...Ian
email (option): ian@wright52.plus.com
I think most 3SW's and 5SW's were built at Coventry.
The rear carrier fitted to the pre pannier 3HW's was in fact the pre war carrier. Here is a rare genuine NOS carrier that I acquired for my 3SW which still had it's old 25 shilling label attached....I wish! Multiply that by 400 times. But still chuffed to find it. Ron
email (option): ronpier@talk21.com
Another one from the temporary Warwick factory,I think they used this factory for about eighteen months so must have built thousands of bikes there mainly side valve models with a few OHVs. 
('Nice restoration ian,it even has the early type toolbox,was this bike at Netley a few years ago,sure I saw it there,steve at yeomans has a 5SW used by the Germans mainly complete in unrestored state,next time I visit there will try and get a photo,only about ten miles away so I pop in now and then.')
That's the one Steve...I delivered it to its new owner at Netley...I bought the 5SW when the purchase of my WB30 stalled at the three year mark...I thought I would never get it so looked for something else that was interesting to restore....
Then of course a deal finally got done on the WB30 so I sold the Triumph as soon as it was completed....
I've seen Steves 5SW a number of times as I stay at his place frequently...I'll be there in a couple of weeks prior to the Stafford Show....Ian
email (option): ian@wright52.plus.com
This is the 5SW used captured and used by the Germans,it belongs to steve at yoemans motorcycles,its at the back of one the sheds so could only take photos from this angle,its not complete but has most of the original German paint over the original khaki underneath. 
A close up of the petrol tank the original tank badge is still present,it was on top of the tank on these early WD Triumphs held on by two screws. 
Close up of the frame number TL 18596 which is stamped on the frame lug under the saddle. 
Front mudguard showing tyre pressure in German. 
Rear mudguard with tyre pressure marking. 
The Germans also fitted rear footrests,the spring clips for the prop stand are still in place,there is no lug welded to the rear frame to hold the prop stand the 5SW had a bolt on stand lug.