Quote Originally Posted by Riff Raff View Post
In addition, you can also take a piece of masking tape and tape along the edge of the rubber blade wear it touches the glass windshield before removal. In this way, when the arms are re-attached then you'll know that they are re-installed in perfect original alignment.
No need for all that. Just align it with the line of dirt left by the wipers at the bottom of the glass.

I was only 'sorta' kidding. Alignment of your wipers is NOT critical. As long as they are close to horizontal when turned off ... good enough.

I've repositioned wipers before just because I didn't like how they sat on the windshield when turned off or to give a little more range on the upsweep.