Help with the battery cable to the stage

Very good afternoon:
I have a Ford Mondeo of the year 99 5p GLX I have a doubt in which I had to stop for it. I want to install the stage to place some speakers on the tray but I can't find any place to pass the positive cable that goes to the battery. Do you throw a hand?
Thank you so much

Hello, look for a site where the vain motor cables go inside the habitaculus does not matter aside because you need to take it in the trunk, it is also very advisable that the cables to feed the stage did not go through the same place as the audio. If you find nothing you can do it with a drill, you paint it and you put a rubber board.