What you need for the conversion so are …

1. the original soffit
2. Tin
3. Dremel with cutting disc
4. Cutter
5. PCB
6. 4x ultra-bright blue LEDs 5mm
7. a piece of wire

First you cut off a piece of board with the Dremel, which is just as long and wide as the original soffit

You now puts the 4 LEDs through the small holes and arranges them in order to always put the polarity is opposite in each case (leave enough space between the LEDs)

The LEDs I have angepunktet schonmal so they do not slip
The trace should now look like in the picture, separated behind and in front of the LEDs will be no contact with each other to exist (and Dremel cutting wheel)
To adjust the shape I abgeknipst the corners with the side cutter

want at the two ends are now small pieces of wire attached by a simple bend it (then make contact with the lamp socket)

Now here is the trace newly formed by the LEDs are soldered together in series (the polarity is here again with “+” and “-” marks)
Tin small wires to the ends of the right thickness

2 Festoon in the interior lighting is of course, we also need 2 LED boards, here we also see again the top and bottom

Functional test with about 13 volts
Blows dranhalten is the first test, the two contacts only briefly to avoid the accident if an LED is an LED or an LED soldered incorrectly bridged

Here we see the finished result, without even with Aperture and once
The LEDs can also reach a bit to be bent to a uniform illumination
If the light is too localized, one can anschleiffen the LEDs with a fine sandpaper until they are weak, because the light is better distributed

for bridge constructions can also take the abgeknipsten LED feet