I have a 1998 1500 sport 4x4. Currently rebuilding the front end and my passenger side headlight flashes bright and dim as the turn signal or hazards are on. I’m thinking bad ground or the multi-switch on the steering column? I checked all fuses are good and all bulbs are good. I’m not great at wiring so any help or advice is GREATLY appreciated. I tried to attach a short video of the issue to this post but I’m not sure if it worked.

Yep, they all ground in the same place. G100. That is the one way down on the rail, in front of the battery. There is a connector down there with like a dozen wires to it. On mine, most of them were corroded, and broken......