ok, so it looks like a billboard is not the best bet from a price/performance standpoint unless we can get a digital one with dynamic content... which would be worth it if we could have a clever campaign that made people want to find out each day's message. Like the old Barbasol ads...
Assuming that is off the table... how about this instead?
You could hire one of these and set whatever route for it you want! Hell, you could hire one to drive Clark's neighborhood in Dallas and just constantly circle the block of his office downtown. Or just stick with KC... either way, it's a pretty good option if you have a good route in mind and can get the media exposure before hand.
My understanding is that it costs around a $1000/day but come on.. it's a fricking sign on the side of a truck.. I bet we could "homebrew" this and cut that cost in half.