As long as you stay with the same wattage bulbs, the wiring is fine and should not need to be wired directly to the battery.
The wipers (I assume you have the euro wipers installed) also work just fine with the U.S. spec wiring. Are you saying the blades park in a different spot every time of just that when they park they are not at the lower edge of the lights but otherwise park in the same (but wrong) spot? If it's the latter, then simply remove the blades and activate the wipers a few times to set the motors at their true park position. Then reinstall the blades in the correct place.