Jeeves,
Here's some sites/pages that may help you out. Not all of them have cockpit shots or have only one or two, some images are kinda small and there's lotsa foreign types which may be slightly different in some details. Also, some of these that do have shots of the pits show modern day instruments. But you should find something useful here.
http://cybermodeler.com/aircraft/t-6/t-6.shtml (No cockpit shots)
http://walkarounds3.home.sapo.pt/harvard.htm (Lotsa Portuguese Texans)
http://www.airventure.de/t-6philip.htm (Only a few here will help with the cockpit, but the rest'll bring back a memory or two for 'ya!)
http://www.robertescalle.com/biography-t6_photo2.htm (ONE photo of a guy in the front pit, but some useful details here)
http://ibelgique.ifrance.com/Aviher/T6/t6photo.htm (Belgian T-6, LOTSA photos, a good number of interior shots but smallish images.)
There was one other which only had 2-3 images that may have been useful, but no matter what I did the link would not post correctly. Oh well...
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