...usually, when you hook up any kind of auxillary lighting, you want to come directly off the battery's positive terminal, with the lightings own circuit...
..generally thru a fuse, switch (toggle?), to the lighting, then back to th' batt's negative terminal..
..it's never good to put more amperage on your scoot's..atv, whatever, oem wiring, than what it's designed for..
..in the past, i've fried some of my scoots oem wiring, experimenting with different types of aux lighting...
peace