I am looking at a Flagstaff hard side to pull with my minivan rated at 3500 lbs. The hitch weight is 341 and unit weight is 2312 dry. My towing calculations on husky come out to 15% hitch weight. As I understand, that is the max I want to be. It has the storage box along the front. When this is loaded, would that put me way over my hitch weight percentage or am I confused here? Or do I load the van and leave camper storage empty?