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I remember a few of these pre '60 Napcos when I lived in Yellowknife NWT late 70's, one a GMC Panel.
Serious wilderness but I spent a lot of free time then exploring unknown trails into the bush by snowmobile/motorcycle which often led to old mine sites w/ vehicles/equipment/core samples abandoned years earlier and there was a Napco Carryall @ one location also a '49 Stude Truck sitting beside it.
Here's the '57 Napco Promo clip on Youtube...
https://m.youtube.com/watch?v=x5LYTkRjdno
~ Pete
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