This is from:
Detroit's Wartime Industry: Arsenal of Democracy
By Michael W. R. Davis
Not they say its 'probably' a CCKW because it 'definitely' has a GMC engine. Its an M135. DUH. Wheels, spare tire, single rears, the cab.
I was going to make a snarky comment along the lines that Mr. Doyle must have been a 'consultant' to the author.... but I think the screw up speaks for itself.