If you get the 100+ watt "HID lookalike" bulbs for $25 off eBay you might very well burn out your harness. If you get a true HID conversion kit you will not put any more strain on your harness than your stock bulbs, provided the HID kit incorporates relays (very inportant) in it's harness to power the system directly from the battery. This way your stock wiring and switch are only being used to open/close the relay and not directly power the HID ballasts.