Accessing underside of 5th wheel
When i took mine down on my travel trailer it was just screwed to the frame about every foot or so. I was able to access what i needed to do by just dropping one side and the back. It is very stiff and when put back i was surprised by how easy ti line up the holes. A word of wisdom is to mark locations of said holes with some type of very visible marker it makes finding the screw holes a lot easier. Also start t a few screws on one side then move to the next and get it lined up with a few others before tightening them all. A magnet bowl to hold screws and a helper if you have one.
Hope this helps.