This instructable is only about the lights of this bike. There will come some more ibles about other parts of the (still ongoing) project.
The idea here was to fit battery powered LED's into the existing lamps at a low budget. Because when towing a trailer I don't want to spend energy on creating electricity for my lights!
If you're interested head over to step 1 for parts...
Step 1: Parts and Tools
I had two cheap LED-lensers lying around on one side and the bikes old lights, dynamo and a toolbag on the other side. I had no more use for the dynamo, so I sold it on ebay and the toolbag was to beat down (torn straps) so I put it aside.
The lensers were taken apart to get the LED's, the leftovers tossed.
Not pictured: two-wire cable, switch
As tools I used mostly standard equipment. Nothing special here apart from a soldering station and terminal cables: pliers, screwdrivers, side cutters, pen and paper, knife, ...
Step 2: Tail light
First I did the tail light. To build in the LED's I had to open it first. I did this by bending open the metal ring which was holding the glass with a small screwdriver. Be careful to avoid to much damage here.
I was lucky, the circuit board with the LED's was a perfect fit. So I soldered on the wires (the clear glue is just to add extra protection and to reduce strain on the soldering points) and glued the circuit board into the housing. After that I put glass and metal ring back on place and bent the ring back (again with a screwdriver).
The hole in the back of the housing I closed with some foam, covered with black taped. Not that beautiful, but it works.