Howdy Cletrac:
I stand to be corrected but I beleive there were ultimately 18 of them, six for each of A, B and C Batteries.
There is one original in the CWM.
Interestingly, the backs were flatdecks with the seats and bins being made up by removing the boxes from four limbers and mounting them on the flatdeck.
So those "jeep" guys now have more proof that the name existed long before the ubiquitous little trucks they love.
UBIQUE! Mike