He said TT, so I suspect that it is a tag trailer, not a 5er. Correct?
I know of a couple of people that have made a framework that is attached to the trailer hitch utilizing the trailers original ball hitch and has some heavy clamps that go around the area of where a set of weight distributing bars would hook up. That way it is not permanant, and easily removed. The one guy built a dolly with wheels, so that slips into place and he can unhook the gooseneck frame and pull it out, so that the trailer can be towed on a regulat trailer ball again. Or to use on a different trailer. That guy that had the dolly setup, also used it on a flatbed trailer as well.