... I had a receiver welded on the tongue which allowed use of adjustable and removable hitch configurations for on road, off road , camp site, and security options. The tongue is actually over 4 foot long at the ball mount...
... I set the hitch coupler at a good tow height and was then ready to take the trailer to get the registration inspection.
This is an interesting design. The receiver box is clearly visible in the early photo with just the shell on the frame, but I can't make out any detail in the complete rig image. I assume the receiver is a 2" box, and the coupler is mounted on a suitable square tube which is inserted in that receiver and retained by a standard pin.
Darrel, you mention configurations for various uses, but what changes? Coupler height, ball size, length... ? Since ball platforms (for the tow vehicle hitch side) are readily available in various heights (including adjustable) and to accommodate any required ball, I wonder why the need for the flexibility on the trailer side.
It is, of course, a relatively unique and therefore "cool" mod!