I used to pull my roadster on an open trailer. I would have to put the back end of the trailer ramps on top of a set of the type of ramps that you use to work on your car. That let the car level out before the trans got to the end of the trailer. A friend of mine said it always looked like I was building a bridge when I loaded my car, but it got me to and from the track.
Another option is to split tail the trailer. Does your trailer have a dovetail on it?
Curtis