You better head to a scale. My 6500 or so loaded trailer tongue weight comes in around around a thousand lbs. scaled when loaded. Don't forget if you have 2x30 lb propane tankes on the nose, battery or (2 in mycase) water and all the other junk we fill our trailers, beds of our trucks, firewood, family, pets, bikes and whatever else is in there that adds weight out of the stripped truck.
I have done the half ton haul too and noticed the difference right away pulling the same unit with the 3/4 ton. Even though I was on the edge experience tells me once you get up there a bit to just do the 3/4 ton for a much better experience especially if you plan on long trips.