The purpose of notifying the police, is in case they get calls of "suspicious" behavior that could be mistaken by home owners or bystanders as "casing the neighborhood". Repeatedly traveling the same blocks is often considered suspicious, but is common during a rallye.
The purpose of sending it the day before (i.e., almost at the last minute) is to make it more difficult for the police to try to talk us out of it? I would try sending it a week early until some bad outcome occurs.
- Mountain View
Here is a sample E-mail. Of course, dates and names (people, cities, and streets) and dates must be changed.
TO: firstname.lastname@example.org SUBJECT: Gimmick Car Rallye Saturday evening in Mountain View There will be a public Gimmick Car Rallye this Saturday evening (Oct. 6, 5 to 10 PM) in Mountain View, as a benefit for cancer research. A gimmick rallye is nothing like road racing. It is similar to a scavenger hunt using street signs. There will be a couple dozen cars driving through the neighborhoods I'm using. The basic route is: (from 101 and Mathilda): Almanor Ave, Mary Ave, Maude Ave, Clyde Ave, Fairchild Ave, Tyrella Ave, Flynn Ave, Whisman Rd., Ellis St., Middlefield Rd., Whisman, E Dana St., Calderon Ave, Church, View St., W Dana St., to Castro. There will be a "checkpoint" on Easy Street along Whisman Park from 7:30 to about 9:00 PM Saturday, where cars will stop along the curb for a few minutes. You might get a report that "suspicious" cars are driving slowly or parking with interior lights on [to read instructions], reading street signs, and then starting off again, perhaps making U-turns or circling around the block to "try again". I'm sending you this email so that you will know what we're doing and may reassure any callers near this route. More rallye info is available at http://www.therallyeclub.org/what.htm -- George Bush, Rallymaster, oct06@TheRallyeClub.org Phone: (650)555-1234
Please add similar info for additional cities.