Well that was just one option in the included instructions. The other was to connect it directly to the battery, by going through the firewall and connecting the red to the positive post in the battery, and black to a ground source. Would this be easier? How would I attach the red?
I guess my first question would be how do you want the lights to turn on? Will you be turning it on with a separate switch of some kind? Also, what kind of lights? I'm guessing an led or multiple led's. Are they connected together or is there a separate + and - wire for each led?
The basic build components I use are as follows:
Switch (if it has a light, it will have three wires - ground, power, and load);
SPST Relay (it will have a ground, an output wire to your accessory/light, a fused power wire coming from the positive batter post, and an input for the load wire coming off of the switch);
Accessory/Light (it will typically have a positive and negative. Usually, the negative is grounded to the frame somewhere and the positive accepts the output wire from the Relay).
Generally speaking, I think most people fuse any wire with power running through it (I do unless I am tapping an existing power wire in the cab that is already fused.) However, when I tap an existing power wire, I'm only doing it to supply power to the tiny led in a switch...NOT to run an actual accessory or to serve as the power source for a relay.