Thank you all for your additional information. I claim that I seated the shackles before installing the bolt, but, if not seating them caused this problem, then I must not have done it. The original shackles had been tightened enough to bow them toward each other. I did not like that plan. My plan with the 2nd nut was to have something for the outer nut to positively tighten onto rather than chance bending the shackles. I can rethink that, if that is wrong.
I forgot about that ugly weld. This truck was hit in 1980 something. The man's insurance company sent my truck to a shop, and I got what I got. I do not know why the shop added those globs. The rivet is still in place. I have an excellent welder who helps me out now, but he was not born until 1990 something.
I added more photos. One better shows that the spring mount is in place. The other one shows my double nut scheme.
I ordered a replacement shackle kit today.
Again, thanks!
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
