Relocate one set of jack stands as far toward the center of the chassis as the center-of-gravity will allow.
Back trailer under that end.
Put a pair of wood sleepers on top of the trailer deck (assuming you care whether or not the trailer gets damaged).
(Optional) take a bar of soap to the top surface of the sleeper.
Lay a wood crossmember across the sleepers. Using a high-lift jack, pick the Jeep up off the jack stands and set it down on the sleeper.
Use a winch or come-along to persuade the Jeep onto the trailer while simultaneously backing the trailer under it (or some combination thereof... basically, don't knock it off the jack stands prematurely).
Once the center of gravity is close to the end of the trailer, jack the back side of the Jeep chassis up with a high lift, lay a sleeper under it, and pull it the rest of the way on.
That's basically how we loaded a Bronco tub/frame onto a trailer. It weighed about 3000#. Loading a Jeep tub should be easy in comparison.