I know this is a bit old. But on the 55.5 and older trucks I always just cut down a gm full size straight axle 5 inches on the long tube. Respline the shaft. And add a spring mount to the long tube 27.5 inches from the center of the passenger side. I use a Ford steering arm on the gm knuckle to get the proper length from the center of the ball joint to drag link hole. And use 73-87 GM 3/4 ton 4x2 tie rod joints to make up a drag link. Here is a shot under my 46 chev.
