Both the 1154 and 1157 bulbs have offset pins so they only go in the socket one way. But the wiring could be flipped so that the brighter filament is connected to the tail light circuit. It's just a matter of how the pigtail is wired. You'd have to apply 6V to each contact on the bulb to check which is the brighter filament and then wire the socket correctly.


Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.