Honestly, I just started cutting metal, no plans. As far as the weight limit, that's a Toyota FJ55 body [ heavy ] and it handles it fine. I made it out of 3" tubing and braced it well.
I had to add a piece in the height of the upright, because the body would hit the brace, when rotating 360 degrees.
I could take better pictures and some measurements, tomorrow, if you like.