Probably a bad ground on that side. To test, attach a ground wire to the socket. I had the same thing on my '69 and this is all it turned out to be. Most likely the rear bulb too.
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Bob (Pa.)
1963 Impala 283
1966 Chevelle SS 409
1969 Malibu 307
1972 Malibu 307
1969 C10 stepside 350
1971 Cheyenne 20 3/4 ton
Somebody stop me...
Looking for Chevelle or Impala parts? Click here:
Chevelle parts for sale
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Bob (Pa.)
1963 Impala 283
1966 Chevelle SS 409
1969 Malibu 307
1972 Malibu 307
1969 C10 stepside 350
1971 Cheyenne 20 3/4 ton
Somebody stop me...
Looking for Chevelle or Impala parts? Click here:
Chevelle parts for sale