What state do you live in?
The reason I ask is some states require off-road lights to be wired through the high beam lights, which requires a slightly different wire routing.
Personally I normally make my own harnesses;
I use heavy gauge wire (determined by light output) between the battery and a relay, relay mounted as close to and between lights and battery, and again heavy wire between relay and lights.
Lighter gauge wire to the in cab switches from the relay.
Heaviest gauge wire I can find for ground, and run directly to the closest suitable ground point.
If you have to use existing lights as signal wire to relay use heavy gauge and tap in close to the lights.
With multiple light sets use 1 switch and 1 relay per light set, don't try to stack as overloading can cause poor light performance and shorts.
Always wire in a fuse appropriate to amperage traveling through the wires for signal wires and power wires.
Use heat shrink for all wire connections and wire looms to protect all harnesses.
Solder all connections and tin all wire ends for best results.