If you have a standard equipment trailer, I don't think it is going to make much difference one way or the other, Brian. You're dealing with a static load if you are trailering your '56, so it won't affect towing performance too much.
Now, if you are hauling a long car or truck that hangs over the leading edge of the trailer so you can still pull the ramps up, you may need that extra clearance. Those extra three inches in length may give you a little squeeze room when backing through a turn. Otherwise, I'd keep the trailer closer to the truck.
