I don't think anyone is trying to derail the thread. If weight is causing an issue with the ramp door it likely will also cause issues with the trailer floor so you may want to address that at the same time.
The door is only temporarily stressed during loading and unloading. The trailer floor will be stressed the whole time the Jeep is riding along. It can definitely be done but you will likely need to pull the door and floor apart and add extra support to the frame and then recover. With the new framing in the door you will likely need extra assist springs or install some sort of a winch system to assist opening and closing.