Told you I'm out of my element here! But I kind of like the idea of a phantom pick up that GM never made as a custom, and that was the idea I had.
In the 50's nosed and decked, not one without the other, followed by shaved door handles with primer spots and you're done.
Subtle touches and attention to detail are all that's needed. On the '58 I cleaned up some of the visual distractions, modified the tail lights and the tailgate. It's more about what was removed from the truck, not what was added.