If I may open an old thread I recently borrowed a book on the Malaya Emergency published on Malaya so not widely internationally distributed, The Malayan Emergency Revisited 1948-1960: A Pictorial History by Muhammad Azzam bin Muhammad Hanif Ghows.
I looked at all the photos of armoured vehicles especially locally modified vehicles. How about something like this as a contender for the unknown hull that was dug up although it can't be this one was the buried hull appears to only have single forward opening.
IMG_2945 by
tankienz, on Flickr
One of the most interesting photos was a Fox armoured car which I have never seen as operated during the Malaya Emergency.
Paul Napier