Problem solved. The paper like insulation wrapping around one of the field coils was damaged and the field wire was touching the housing. The insulation wrapping is very brittle after so many years and breaks easily. I put some insulation tape on it for now, but would like to restore it as it was.
Any ideas what to put on it or maybe best to take it to a professional for the right treatment?
1958 T-Bird "Trovão Rosa" - "Rose Thunder"
Thunderbird registry #61670