I am interested in building a Skoolie but I dont see any talk about towing a trailer. I want to tow a trailer weighing close to 2,800-3,900 lbs (empty) with a 3,000-3,500lbs load. I need to know if Bus engines will haul this additional load, and at a speed of 70mph. What is needed to add a hitch and any other considerations. Has any research been done on this?