ambient lighting

Has anyone retro fitted this? I had it in my Golf.. a lovely soft red glow... would like to explore doing it in the van... I could do it fairly easily by drilling a couple of holes and fitting led s in them.... I'm hoping to be able to do something a bit more professional than that....

Does anyone know if there's a permanent live i can tap in to within the tailgate? I'm wanting to fit some led's into the hardboard panel at the bottom of the door, which when open will illuminate my work area (at the back of the van) My options are either battery powered or if i can grab a...