A quick mock up of some doors made from 18"x24" signs.
The bottom of the tire is 12" from the ground. The clearance from the front of the door to the bumper is about 2".
Door closed...
Door opened...
The bottom of the tire is now at 18" from the ground. The front of the door is just touching the rear bumper.
Door closed...
Door opened...
To secure the door from opening on it's own, I'm thinking about drilling a hole through the support from (once I build and attach them to the doors) so I can run a length of ½" PEX pipe through it and into the extended side vertical supports so it will lock it in place.
I'll probably add some reinforced brackets perpendicular to the inside of the doors so I can put a top to the doors.
The clearance from the front of the doors to the back of the tail lights is about 10" when the trailer is sitting level to the ground.