Since you shined all those grounds up under the hood, they should be good. I can't remember if an A body as late as yours has separate flashers for emergency and turn signals. Did you have the dash frame out? I can't remember. When I remove a dash frame to paint it and door jambs, I always sand a place to bare metal on both the door jamb area and the dash frame, where the bottom mounts of the frame bolt up at the door jamb, I use some of that dielectric grease like you put on battery terminals at those points so they make a good ground connection and don't corrode. Chasing electrical demons in a car is a pain in the butt, and all of the stuff I've mentioned I learned the hard way over the years. :BangHead: LOL
