I'm starting to see where you're going with this and it sounds pretty good. On a side note you're math is a little off, 1% or 200- 300 is only 2-3 cars

. I have no problem with this being more of a Seattle thing, I'm more then willing to come up now and then and in return every once in a while we'd have to alternate between Ptown and B.C. (only fair). In the NW though I feel that Seattle has the most active members so the majority of meetings would take place there.
I'm not saying we can't get over 15 cars to show up either, what I am saying is that people that normally show up to these events are car enthusiasts. The percentage of people that are enthusiasts that drive SVT's is fairly high, whereas the percentage that drive non SVT's is really low. My point is that targeting the non SVT's is going to be a very hard process due to the fact that you're going to have to distribute a lot of flyers. Don't take this wrong, I'm all for getting as many Contours as possible to show up, I'm not some SVT elitist. Maybe looking into getting some Cougar guys and possibly Focus people to show up would allow more publicity to this whole thing.
Another thing is organization. I hope you realize how hard it is to organize a gathering like this. At even 15 cars the logistics are hard to manage. If you start having larger get togethers then say 30 cars you might run into some legal issues (state gathering laws, traffic problems, etc.). I'm waiting to hear some others ideas, this isn't impossible and a little more organization within the NW would definitely be welcome...you have to admit most of our G2G's aren't the most structured events ever, though that is half the fun.