I don't see how this works. The axle cuts a path through the space above the deck. If the floppy bit is decked you can't have anything behind the axle when you change states. Flipping that tail up would require some form of power assist.
A better way to do this would be to mount the wheels on excentric hubs, which in turn are welded to the axle. Now a single hydraulic cylinder can rotate the axle by about 135 degrees and raise the trailer by about 10 inches.