Vincent,
Could it be that the door has been recently replaced? It seems to have a slightly different colour and that could also be the reason for the missing data plates.
I seem to remember that the Ford cab13 nose with lettering "FORD" under the headlights, suggest it was built in 1943(?) Hopefully anyone can confirm.
There is a thread
here that gives some ideas where to look for a possible chassis number. Sadly not all trucks were stamped with a number!
Alex