Okay, here's a longer explanation of what I intend to do, just to try and make this clear:
There will be a track. This will be a continuous track. A deformed circle, if you will. On this track will be two or more vehicles. Each vehicle will be designed in such a way as to allow players to stand on top of the vehicle. So long as a player is of the same color as the vehicle in question, the vehicle will move around the track following a predetermined path. There is no timer, there are no capture points, there is no way to win or keep score other than by visual observation.
The carts I have in mind are the truck prop found in 2-Fort, with the wooden sides on the truck bed. Mostly because it already exists, has a definite area for players to stand, and has both red and blue versions.
Failing that, I'd obviously have to make something. And given my modeling skills, I'd either have to hope I could make something decent in SketchUp and import it, beg for assistance, or use brushes. So I'm hoping that the trucks would work.
Ideally I'd have six (or more) vehicles on the track with overlapping (if not intersecting) paths, which may rely on varying elevations to pull off, along with definite start/finish lines and an option to reset all the vehicles at the start/finish line. One that preferably could not be used to grief.