I built a junction box to go on my roof rack for the two sets of lights I plan to install, so I didn't need all six (or even the four). The single relays worked better and cheaper. I bought a simple relay box off of Amazon and wired up two relays. This gave me the flexibility to have lights in more than one location (may put some on front grille, too) and not have to buy more relays than I need in any one spot.