76 Dart no lights

Don't START at the welded splice, you have to tear the cluster out. There are several other points you check FIRST

Very first is the TAIL fuse as I mentioned earlier. Both sides of that fuse should be hot

If that is dead, on BOTH ends find out if other "hot buss" items work.

You say your hazard flashers work? They are powered by the hot buss. This means the welded splice IS furnishing power to the fuse panel

Headlights. Start at the dimmer. If no power there, got up and pull the light switch out so you can access it. Know how to get the knob out? Reach up underneath, (disconnect battery ground) pull the siwtch out, and find/ feel and push the release button. Shaft and knob will come out

Like this:

WiringLiteSwBack2.jpg