I have just purchased a roof rack for my D90. I now want to install 4 spot lights across the front of this, however am concerned about the wiring aspect. It can't be that difficult, but I am after some guidance. Has anyone done this, or is anyone aware of a website giving really easy advice? Grateful for any advice anyone has. I am content for a separate switch to be fitted to operate them if that makes it easier than wiring into the main lighting circuit. Thanks.