I would check the grounds. If one side doesn’t have a good ground, it will look for the path of least resistance and use the other bulb as it’s ground.


Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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