Re: 1965 fastback electrical problem
The turn signal switch is at fault. By design the switch shut's off the brake light and use's that circuit for a turn signal even when braking. Your switch is shorted inside letting current flow thru the brake light circuit to the turn signal circuit in front. I have a nice free HowTo video uploaded on my site that outline's the procedure to replace the switch.
Chris "the Doc" Ingrassia
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