towing

Towing a car across borders

Has anyone towed a car across a border yet? 

I have an uruguayan car here in Chile that needs to return to Uruguay before August but it has basically broken down. So we were thinking of towing it with our Ford E-250 van (registered in the U.S.) because it too has to leave the country in the next month.

My fear is that there is some rule against doing this. We will purchase a tow dolly to do it right, but if anyone else has tips or knows of where I can find rules regarding this, I would greatly appreciate it!