Generally all of these types of quirky issues can be traced back to bad grounding. I chased a strange interior lights issue on my '67 years ago, and the culprit was the under dash light housing loose from its frame. The grounding for most, if not all the lights is housing to body contact. The tail lights are the most prone. Need to grab them and grind against the housings every so often to get a good ground. Front turn signal housings are similar. Rust at the housing screws can mess those up too. Also possible your turn signal switch went out. Those are known to go bad. You may have multiple ground issues as well, making it more difficult to isolate. Keep checking everything.
I used to be indecisive. Now I'm not sure. I feel like I am diagonally parked in a parallel universe. 1968 400 convertible (Scarlet) 1976 T/A - 455 LE (No Burt) 1976 T/A New baby, starting full restoration. 1968 350 - 4 speed 'vert - 400 clone (the Beast!) 1968 350 convertible - Wife's car now- 400 clone (Aleutian Blue) (Blue Angel) 2008 Durango - DD 2008 GXP - New one from NH is AWESOME! 2017 Durango Citadel - Modern is nice! HEMI is amazing! 1998 Silverado Z71 - Father-daughter project 1968 400 coupe - R/A clone (Blue Pearl) (sold) 1967 326 convertible - Sold 1980 T/A SE Bandit - Sold
