UPDATE: At bottom is a printed version of the plate listed on eBay. A few of the pics show the truck with the high middle cross piece on the grille, which helps date it.

View all the information on eBay

“8 x 6 x 1 inch
“Let us demonstrate America’s lowest priced 4-wheel drive truck”
“4-Wheel Drive Jeep Truck”
“Willys…world’s largest makers of 4-wheel drive vehicles”

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Originally published April 14, 2013: The ad is from 1956.

“Original newspaper ad , 8 x 8 .”