This post has been edited to clarify and correct some earlier information.
The Panel truck “boards and strips” setup was used through 1949.
From 1950 to 1955st, Panel truck rear floors were 3/4” plywood with grooves for the metal strips.
I know that's true for Subs, but are you sure that applies to panel trucks too? In Suburbans the board floors were superseded by plywood floors to prevent dust entering the passenger area. Since the rear area in a panel truck was for cargo, not passengers, I have heard that the change to plywood floors came much later (different assembly plants?). Anyway I sure have seen a lot of 50's panel trucks with board-and-strip floors. Maybe they did what our OP is considering?
