I had the local High School Vocational Welding teacher make me up an attachment for the king pin box.   I took him some pictures and some measurements and let him have at it.  What he made could probally hold a tank.  It also used existing holes so there was no welding to or drilling into the pin box, so that I can remove it to transfer to another camper or to avoid any warranty related issue some  dealer looking out of a warranty repair using it as an excuse.   The only oddity is the metal wings that hold the level, the teacher misunderstood me and the picture was not clear enough.  He made a separate bolt on hinged attachment for me to bolt the level to, when I explained again and showed him the level he simply removed it, cut it into and did some welding to make it wide enough to hole the level.