Been out checking and found that the 3/4 ton does not seem like it would work for the ball joint appears bigger,
Did crawl under a 68 truck I have and found that they appear the same,

took one out and appears the ball joint is shorter in length but same diameter hole which is fine since I have new ones and these arms are in great shape so I found my donors, but didnt want to rob from the complete 68 shortbox stepside I had saved for maybe a future project but hey 71 first, I say....