I don't know if they label items differently for the '40, but in the AD trucks the "hole cover, battery floor" is just that, a cover for the battery which fits into a rectangular hole in the floor. The other item, "floorboard section, fiberglass, 4-speed" is the removable center floor section over the transmission.
Are those the items you're looking for, or do you need patch panels? Again, AD parts catalogs have floor, toeboard, firewall, inner and outer cowl panels; I haven't looked for '40 parts... yet.