The tech tip on this upgrade does not elaborate on the necessary modifications to the pitman and steering arms so I hope to clear some of it up. Although I am a fan of original equipment my tie rod ends had been converted to the tapered type in the past so I decided to just keep with the theme. Reference to "tie rod ends" in this thread refers to thier use as drag link ends.
I bought the 3 components as described in the tech tip and although perfect in length; the short pc. (Napa#269-2078 aka Moog#ES-403R) has a 10 degree included taper angle and the longer one (Napa#269-2225 aka Moog#ES-288L) has the more common 7.15 degree which is also known as 1.5" taper per foot. I'm a big customer of CNC tool and cutter grinding and so getting a couple endmills ground was economical for me and I will be happy to forward them to the next bolter going this route who promises to forward them on after use.
I carefully machined a v groove in the back (swaged side) of the pitman arm to determine the actual size where it is spread out which is 3/4". With a shank size of 5/8" this means considerable material needs to be removed to eliminate all swaging if a grinder is used. Drilling 1/2" thru and then countersinking will result in much less parent material removed. See
here and
here. With the pitman hole the same size as the large end of the taper; welding up the hole is necessary before drilling to 1/2" and then taper reaming. I used the 10 degree mill on the pitman arm to mate with the longer tie rod end.
With the knowledge of the stud and swaging size I decided to try a different approach with the steering arm by cutting off the ball, milling the flange flat, and drilling/taper reaming directly in the remaining portion of the stud which worked fine and eliminated welding. See
here and
here. As taper milling is one of the highest torque machining operations I'm certain if it wanted to move it would have done so while cutting so I'm confident of integrity.
Here's the end result which is a big improvement in my case and I hope some of you find this info useful.
