I have the shackle repair in place. Poster Twin Jimmys provided a set of original shackles. They are 3/8" thick and fit perfectly onto the pins. The replacements are 1/4" thick. My earlier photo shows the shackle pins to not be centered within the spring or the mounting bracket. I do not know if they moved after assembly or if I installed them that way. That does not seem like something that I would do, but I do not know. Centering the pins leaves them protruding 5/8" out each side. I adjusted both pins on each side to that. I used a c-clamp to ensure that the plates are tight onto the pins.
One shackle in the new kit fits well. The other shackle looks like the holes were chewed, rather than cut, and it does not fit fully onto the pins. Because of receiving original shackles, I did not have to use that. Thank you to Joe H for the locknut part number. I may get those later. The provided locknut has 5 (maybe 6) dots marked. The closest that I can match to a chart is Grade 8. I did not use my 2nd nut in this redo.
Later today I will have a test ride.
Thank you to everyone who offered advice.
1950 GMC 100 Panel Truck, 1958 270, 3-spd Saginaw with BW OD, 3.73 12 Bolt Differential from a 1966 C10, Front Disc Brakes Bought it in pieces 9-1976, driving since 6-1978 Follow in the DITY
