If I remember correctly, starting from the switch, take the brown(black?), yellow, and white wires (3 of the 5, I believe), and cut them about 5 inches before they go into the harness. Take a wire cap nut, or similar electrical connector, and connect all 3 of these wires together. Then you will always a have a headlight and tailight. I think the other 2 wires can be removed. But double check where they go first. If there's a red(purple?) one it goes to the horn, and is all but useless. The last one may be the 'flasher' button, if it is, it's also useless.
Does that sound right?