You mean the black and gold piece of pure badassness?
That's the one.. Ol' Smokey cut and carved on that Chevelle body something fierce.. Reduced the frontal area, chopped the A pillars and added more rake to the windshield, narrowed the car, and lots of other body mods.. And made the damn thing fit the templates.. Standing alone the changes weren't very evident. but place it beside a "normal" Chevelle and the differences stood out like a ***** in church...
In the early days of NASCAR racing, body modifications were very limited.. In 1957 (or thereabouts), Smokey ran a 57 Chevy sedan.. Now everybody knows about the vent inlets above the headlights.. The vent outlet is in the kick panel.. Well, Smokey figured a way to reduce frontal area without actually changing the frontal area.. He plumbed in a large tube that started at that vent inlet opening and ran the tube through the fender, firewall, inside of the car, all the way to backup light openings in the rear bumper. The theory was that some of the air hitting the front of the car would pass through the tube and exit the rear, reducing the size of the "wall of air" the car has to penitrate. That simple modification gained him 200 RPM down the straightaways..