My low beams don't work, and to follow the wires, you need to locate a connector C-2.  It's a black connector, similar to the ones on the firewall junction panel.  It's probably behind the radio, but I only looked near the fusebox & relays so far.  Maybe someone bumped it when fixing the heater core, since that's about when the low beams started acting up.  It's near the fuse links in this graphic.  It also goes to the kickdown switch and kickdown solenoid.

The High beams work fine.

 

 

I found the connector.  It is on the firewall under the heater fan, next to the transmission tunnel.  there is also a Green connector in that area.  Please refer to the photo.  The ground wire from the low-beams goes through it to the dimmer switch, so it's important to clean the terminals with DeOxit.

  I think mine became corroded from some water entering through the holes where tabs on the ventilation air intake grille goes through the chassis below the windscreen. 

Make sure you have the plastic grille sockets glued in with a good sealant, so you don't get water coming in when driving in the rain.