If it were me I'd leave the leveling jacks up go to Harbor fright get several bottle jacks big enough to hold the weight of the MH. level with blocks under the wheels. Then use the bottle jacks to stabilize the rig from movement and a little extra at the rear to raise it enough to use the door.
I think the rear of the unit is sagging and your adding more weight by putting more twin beds in the back in the long overhang you already have. I know you have to work with what you have and this may help. But with the weight in the back I'd be concerned when it came time to drive it down the road.
If it sagging a talk with a good welding shop or mobil welding truck may be able to reinforce the rear frame.
