Today in WW II: 11 Dec 1941 Germany and Italy declare war on the United States and US reciprocates.   

WC-55 Truck, 3/4 ton, 4x4 Gun Motor Carriage Dodge (G502)

The 3/4 ton Dodge WC-55 Gun Motor Carriage was manufactured by Dodge during 1942, as the platform for a temporary solution to the need for an anti-tank weapon. A 3/4 ton WC-52 Weapons Carrier was modified by mounting a 37mm M3A1 anti-tank gun along with other equipment and small changes. The combined modified weapons carrier and anti-tank gun were designated the M-6 Gun Motor Carriage (GMC).

Visit the linked page for photos and more information about the M6 GMC.