
Tracing the wires on my BC Coupe (Euro market), I've identified from left to right:
Interval wiper (black box)
Cooling fan relay (grey-silver box)
Underhood light (gold)
?? (odd black box set off from chassis, under throttle cable)
Alternator charge indicator (gold)
Headlight relay (silver)
So, what is that odd black box? Voltage regulator?
Also, did all quad-light 124s have a headlight relay, or is this Euro only? If I were to use relays for all the headlights, should I ditch the original relay and use separate, new relays for the high and low beam circuits?