How to convert brake light to fog light (help needed)

[1990timeismoney]

Hi all got a mot coming up and got no fog light. on my old gt the bottom brake light had wires cut and made into a fog light,want to do the same again but have no idea what wire need to be cut etc.

any advice or diagrams would be much appreciated.

thanks

[yaristurbo]

Need to install fog light switch fused live to bulb holder and earth to chassis

Or find a friendly mot tester

[1990timeismoney]

Ok thanks ive installed the switch its just now which wire to cut is that all I need just a positive wire and earth.

Thanks

[yaristurbo]

Positive with fuse 10amp(someone will clarify) and switch.

Bulb holder

To earth