(The pics were also in a recent post in General.)

I'm not sure if mine is original equipment (I doubt it). The bracket grabs the bumper support and was there when I bought my '48. I got the light case (with burned out 6-volt light) at a swap meet. It connects to the bracket via a ball and socket joint. When I went to 12 volts, I found a NAPA #4412A fits perfectly.
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Fog Light Bracket
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Fog Light On
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Fog Light Pattern
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Turns out my copy of "Chevrolet Accessories for 1948" shows no fog light fixture or replacement bulbs. Maybe they were all aftermarket with various designs.







1948 3/4-Ton 5-Window Flatbed Chevrolet

34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.