Re: LED Headlights
Using a power wheel (W=VA, where W is watts, V is volts, and A is amps) and assuming all modern vehicles with a 12v DC system, the headlights/leds you are talking about stating 120 watts of power, will be pulling 10amps of current.
The stock bulbs are rated at 55w/60w, low beam and high beam respectively, meaning they draw a current of ~4.5 and 5amps. Doubling the current draw will put a great strain on the stock wiring.
This would be a high risk if you decided to run these bulbs and will almost certainly damage some part of it, whether it be the harness or wiring itself
You have a general idea of how led's are supposed to draw less power, but with the wrong approach. LED's, although rated in lumens instead of candella, generally put out the same amount of light with less power. This means that with the same brightness from an LED bulb vs an incandescent bulb, you would be drawing less power. Also, keep in mind that LED's are still in essence a diode, so manufacturers will often put the 6v-12v ratings to help understand your current draw. LEDs will light up at a certain wattage, not necessarily just current or Volts. If it was decided to wire up your aux lights in series from the same source circuit, then the Voltage would be shared between the 2 bars, dropping it to 6v per bar instead of 12v. This would in turn increase the amp pull to the bars so that they would light up. However, this is subject to the circuit you are adding to and would really only apply if the 12v source was the battery itself.
Hope that wasn't too confusing.