What I like about the barn doors when topless is I don't have to unlatch the spare to get access to the bed.
I really do like a set of barn doors on the back, but I really don't want to drill new holes in the tub for the hinges. I thought about using barn doors with just the upper hinge, but I think hinge placement (and the hinges themselves) are different between barn doors and ambulance doors. I do not see myself loading much in the back for the foreseeable future and passengers should be able to step over my gate(with a little vertical help!).
I used the justification that it was too hot out to do anything in the outdoors today, so I was able to work on the rear barrier (cannot really call it a tailgate when it will be in a fixed position with no "gating" ability).
I started by cutting rubber cushions for the rear hinges from my inner tube, installed the hinges, and clamped the vertical ends in place to get measurements for the horizontal pieces.
I used the chop saw to cut most of the bar stock, although the hacksaw was used later on for more intricate work.
My mediocre welding ability soon had a rough framework in place. I was proud that my angles were all straight and square. . . until I test fit the assembly in the tub only to find out the tub is less than square. There is a slightly larger gap at the bottom on the spare tire side -- but that should be hidden by the tire so I carried on. I elected to put the upper horizontal bar in this position so I could catch it with the outermost bolt hole on the hinges.
The level says we are dead on. . . as long as the floor and tires are flat/even we should be good.
Instead of angled pieces in the middle (from my drawing) I kept things simple with another single horizontal bar. This was for ease of mounting the license plate holder. Not much of the gate will be visible when all the bits are in place anyway. . . intricate bars at various angles probably would not be appreciated.
A finalish mock up with the license plate clamped in place, the vertical bars shortened and capped, and a couple triangles on top for some extra geometry.
You can also see my rear exit exhaust. I left things there for the day so I could decide if I liked the angled pieces at the top (I believe I do). Final placement of the license plate holder will happen when the tire carrier is mounted so I can get everything positioned just right.
This setup should make the back of the 40 look more complete and keep most of my precious cargo from rolling out. Considering I have about $50 in materials (with a good bit of bar left over but not counting welding wire, bolts, my time, etc.) it was an economical solution as well. It is not perfect, but add some blue paint and I will be a happy camper.