Nice work.
Just as an FYI for you and others contemplating such a project, the roof trim (extrusion) and the cast aluminum corner brackets can be bought from Northstar Campers factory.
Northstar now uses 'Swagman' racks on the roof.
There is a solid wood perimeter frame just inside the roof radius that is 2 1/2 inches wide.
This information is from the owner of the company, Rex Willet.
Propane tanks are quite sturdy and no one plans for collisions. My issue with either the WH and propane tank being behind the rear axle is that it alters the weight distribution and center of gravity. It just makes the most sense to me to keep as much weight as possible between the axles.
Be very skeptical of Progressive. One of the consumer groups did a comparison of insurance cost of several companies and found that Progressive was consistently higher than ALL the rest.
Personally I got quotes from Progressive and Geico for a motorcycle policy and Progressive quoted double the...