Brico sacado de una web "compañera" africana (si, es la ola africana, jaja)

http://www.opelownersclub.co.za

copy/paste.

Some Opel Mk.3 Kadett owners might have once or more replaced a rear cluster bulb, some might have noticed that there is actually 5 bulbs, 4 of which are usually used. There is however a way to use this extra bulb to aid in making your car much more visible when braking. This is an DIY guide how to do just that.

Firstly remove the bracket from the rear light cluster and disconnect the wiring plug. This is what you will see (this is the right hand side one).


As can be seen the lower left bulb is the currently unused one. The connection that needs to be made to share a circuit with the existing brake light is shown also.


To ensure the connection does not get loose (due to the weird surface on the metal connections, you might need to scrape or roughen the soldering spots with some sanding paper or a sharp object. Use a small piece of wire, and carefully solder the two sections as displayed as not to cause shorts or blown bulbs and fuses.


This is what you will end up with if you do everything correctly. Much more visible to people tailgating you

Thanks to 200Darter on the Opel Owners Club Forum for this little gem

Esta bien y parece facil, pero por esta regla de 3, que pasaría si encendieras la luz del antiniebla? se encendería tambien la del freno? Bueno, ahi queda...