I would expect LED spotlights to pull relatively little current.
If that's the case, the power you need is already on the relay plates, just above the headlight switch. There are studs for various power sources, e.g. constant power, switched with ignition, switched with ignition and load reduction relay, depending on when you want them on. You'd just need a ring terminal and your own fuse. The numbers and wire colors, or a quick test, will tell you which is which.