Nice idea, but way, way too easy. I'd recommend either upping the charge to 1 sig or making the ritual more complicated. For example:
Walk around the car clockwise reciting the names of every serial killer that owned a panel van. This must be done in a parking lot at midday, preferably on a weekend. Then, at midnight of the same day, in the same parking lot, spend one hour in your car driving around in a fashion as one would do if looking for a parking spot during the day.

Just trying to work the symbolic and paradoxical nature of UA magick a little.....

I'll definately say that Wiretrippa's suggestion is much better and more atmospheric - and it's more likely to have someone ask what the hell you are dong (evil GM smile)

Duly noted. By making the ritual a cost of 1 sig makes the character(s) think of how badly he wants to blend into the background.

I was thinking more of a a quick effect than a planned action. Something the character can do when he wants to steal a car, or just leave a scene in a hurry.

A White Van is always seen leaving an area after something has happened. Be it a UFO citing, a child abduction, even an act of terror.

Example: The Peck (A Dipsomancer) pulls into a roadside store to get a bottle of Jack. He walks into the place to see the clerk lying in a pool of blood. The Peck panics and sees a car pulling into the gas pumps. He then steps outside does the ritual and jumps into his Dodge Charger and pulls away.
Later while being questioned by the cops the occupants of the other car tells police that a white van was parked here and an average fellow with an average build behind the wheel.