in 1941-42 they were actually WC (weapons carriers) and not Power Wagons, here are the different models.
The WWII Dodge ½ ton WC were produced in 3 series from fall of 1940 to May 1942.
The various 4X4 models are as follows
WC1, WC12, WC40 Closed cab weapons carrier
WC3, WC13, WC21 Open cab weapons carrier WO/W
WC4, WC22 Open cab weapons carrier W/W
WC6, WC15, WC23 Command Car WO/W 6 volt
WC7, WC24 Command Car W/W 6 volt
WC8, WC16, WC25 Command Car WO/W 12 volt radio
WC9, WC18, WC27 Ambulance
WC10, WC17, WC26 Carryall
WC20, WC21 Closed cab and chassis
WC5, WC14 Closed cab pickup, WO/ troop seats. The bed on these trucks were never drilled for either the cross seats, or the longitude seats.
WC43 Closed cab W/telephone body
WC11, WC42 Panel.