My tool was piece of wood cut to fit inside the lower control arm between the wide ends, and a can of spray paint. Before I removed the old shaft, I snugged the wood jig in the arm, under the shaft, spray painted where the holes were and simply matched them up when installing the new shaft and bushings in the lower control arm. I am sure that the special tool j-3184 is just a device to center the shaft in the control arm, and a ruler would work just as well once you do the rithmetic. Anyway it worked fine. Now just need to figure out to determine if the steering knuckle support or maybe the spindle is bent on that side because I just can't get a Zero degree castor with pin fully adjusted out. The book says Kingpin angle 3 1/2 to 4 1/2 degrees, but I haven't figured where/how to measure that, or if I even want to. Have it all put back together and running nice now, and replacing all the pins/shafts was a bear. Guess I will have to do it ...later...
Any help on how/what to measure would certainly be helpful.