Hello,
I have two Bedford MW manuals and both mention that the standard MW is fitted with 'run-flat' tyres.
The June 1941 drivers handbook says at paragraph 60, p44:
'The standard 15cwt MW truck is fitted with "run-flat" tyres and carries no spare wheel"
The January 1945 drivers handbook says Task 16 D, p53:
'Inspect spare wheel mounting and tighten if necessary. No spare wheel fitted to vehicles equipped with Run-flat tyres'
Take your pick!! As with the Fordson WOT2's (mentioned in a Ford diagram I have. RF's changed the vehicle letter B,C,D etc as well as the Body style) it seems many 15cwts were indeed originally fitted with Run-flats.
Regards
Gunnerop