The space under the seat IS the tool box.
Your truck would have come with a jack and lug wrench.
But not the hand crank, that was discontinued sometime earlier. Yes, there is still a hole in the grille and fitting on the dampener for it, guess they did not bother to eliminate those. Another item you might be interested in was the tool kit, but you did not mention that, it also was eliminated as stock and became optional in 1949 I believe.