The prototypes have been bolted on (not welded). Today we submerged them in water and were pleased to see that no water leaked through. Welding could be an option for new users. However, bolting allows existing users to upgrade. What do you guys think? We're going to continue to use and abuse these to make sure they hold up to the stresses of adventure riding.
Here are shots of the prototype mounting system. First from the outside of the box and then from the inside. The Roof Rack has 4 "feet" and each foot will have a mounting point.