This was originally distributed as a file called litewiring.bmp through the IMON mailing list. I searched for it and couldn't find it, so I recreated it here, as well as attached the scan, of the copy, of the printout, of the attachment from the email. I'm about to do this myself, so I'm going to take this, as well as what's out on merkurencyclopedia.com and combine them into a new article.
Dec 2020 update: Here is what I did in a new 23turbo article.
The wiring information and requirements below are shown for one side only. Wiring will need to be copied for the other hand side. The below pictured 4 relay set-up will allow standard or high wattage bulbs to be used. As a minimum, the high beam and driving lamp circuit must be relayed (see supplement). The low beam relay could be omitted only as long as a bulb with a 55 watt low beam rating is used, in this case the factory yellow low beam wire can be connected directly to the low beam pin on the euro lamp socket (see supplement). As an option for the driving lamps a switch may be added between relay terminals #'s 87a and the driving lamp pins on the euro lamp socket. This will allow the driving lamps to be either on or off with the high beams without a switch the driving lamps are on with the high beams.
Euro Lamp Socket (TOP)
- City Lamp --> use factory b/grey (driver side), r/grey (passenger side) from smaller running lamp inboard of original headlamp
- High Beam --> run wire from position #87 relay B
- Low Beam --> run wire from position #87 relay A
- Driving Light (conv?) -->
run wire from position 87a relay B
- Ground --> use factory brown ground wire
Relay A - recommend Hella # 87106 type
- #30 - 12 volt direct from battery (install an in-line fuse)
- #85 - ground
- #86 - original factory low beam wire (yellow)
- #87 - run wire to low beam position on euro lamp socket
Relay B - recommend Hella #87118 or similar type
- #30 - 12 volt directly from battery (install an in-line fuse) or jump from #30 on relay A
- #85 - ground
- #86 - original factory high beam wire (white)
- #87 - run wire to high beam position on euro lamp socket
- #87a - run wire to driving lamp position on euro lamp socket
Notes: use Hella or similar type relays, quality wire, and crimp-on connectors (12 gauge minimum). Lamps are supplied with 55/60 watt H4 bulbs for low/high beam and 55 watt H1 for driving beam. As long as the above instructions are followed (all relays installed) even more light output can be achieved by fitting 55/100w or 80/110w H4 bulbs in the main lamp and 100w H1 in the driving position.