I have some aftermarket lights similar to the ones in the picture. In the car I salvaged them from they were conected to some white wires. Unfortunately I did not take a pic nor remember what wires they were. The wires that were used came from the handle and lock location also ran strait to the light no wire tap or splice....
Where do those hook up? Those are pretty cool looking.
They may have been hooked up to the door lock actuators, however the first gen legacy does not have an actuator in the driver's door, so that won't work for it. Everything else powerwise only energizes with the key in the ON position. If you need power when the car is off, I'd suggest running a power wire from inside the cabin to the door.