IMO, the best suggestion I've seen so far was the one about removing your bumpers and installing the SVTs when you get there. Your mileage down may suffer slightly, but no much. As for people seeing your car minus bumpers, think you'll ever see that car you passed again?
Pros:
1. You can drive your car to get them
2. You won't have to buy anything new to make it work i.e. bumper hitch
3. You won't lose any interior room, high comfort level
4. You'll still get better mileage than if you took a minivan or truck
Cons:
1. Your car will look ghetto for six whole hours
Seems pretty obvious to me! Good luck which ever way you decide!
