From the factory, most tires have a spot of ink on the sidewall where the valve stem is supposed to line up. Some don't do this...I think the last set I did without a mark were Pirelli 19s for an X5...Diamandis 285s or somethings. From everything I've learned, it doesn't really matter if the marks are aligned, the wheel with either balance out or it won't...the weight difference doesn't matter.
best, whit