You could always run it single shear and see what happens. How much of a pain is it to replace the threads in that arm? Can you just replace it, or is it part of the knuckle? Welding a couple brackets on seems easy compared to repairing threads, but if it's easy and inexpensive to replace the steering arm on the knuckle, run it!
My main concern is that it's about a 9" long bolt that has the drag link on top and then the tie rod below the high steer arm.
So if that bolt snaps I lose steering. Now the ram will be doing most of the work but there is still going to be stress on that bolt. The tie rod is double shear but it's the drag link that takes more stress. I think for the hour of fab time I'll just make the double shear bracket and be done with it.