An alternative may be to back your Dart into the trailer. You have more car behind the rear tires than you do in front of the front tires. Don't know how that might effect your 5th wheel balance and hitch weight.
That may be an option. It would also help to take some tung weight of the truck. When I get home it is dark out so I am waiting for this weekend to see what it takes to get her in there.
