I can only comment on the vehicle I have owned or worked on for others and as yet haven’t come across “Rexne” in ex-military vehicles of that period, that’s not saying it wasn’t used. Austin is credited with manufacturing trooper bodies though there are two types distinguished by the shape of the side panel pressings so suggest the panel pressing may have been done elsewhere, sorry digressing. Interesting post and anyone saving a British WW11 lorry gets my vote