I'm new to this site so my timing may be outdated for your purposes.
We have a 1972 model Ventura which we have towed for 250,000 km from Newfoundland and Labrador to Alaska and all parts in-between with no problems.
The front of the body is sloped forward at the middle allowing the trailer to ride so well that you don't notice it is behind you. Ours has the square, boxy, corners and not the more modern rounded corners. We like this feature as it makes it easy to work on the interior and actually gives more usable space.
Our advise is to reactivate the electric
brakes if they have been disconnected, or install them if they are not already on the trailer. This greatly increases your towing capacity and your braking ability. It is required by law to have the electric
brakes functioning if the trailer is equipped with them.
Happy Trails,
Hobbit Hilton & Crew.