I don't know what you're saying. As far as African-American anything,they probably stole it.Well I try to get as much info as possible from other peoples accounts. But then again, I never assumed that they all new exactly what they were doing. African-American ingenuity had to come from somewhere.
85.5-91 had kp also. I gave him two links. You can lead a horse to water.....You should search, there is a ton of information on this website rather than ask for people to give it to ya. The 78-79 has king pins the newer one has ball joints. Ball joints wear out and King pins can be rebuilt and serviced. The kingpin axles leaf perch is further inward that the ball joint ones also. Which means the tire will be further away from the leaf spring for turning radus.
If you don't know the difference in axles you might not be ready for an sas.
The only difference is that the 78-79 has the center of the pinion moved over about 3.5" (the entire center section is moved over). So you have a slightly longer axle tube on the short side (compared to the 80's style Dana 60), and a slightly shorter axle tube on the long side (again, compared to the 80's style Dana 60). Otherwise, they're the same. It just depends on your application. Generally, the 78-79 is more desireable. But the spring pad width may work better with the 80's style Dana 60. I believe the spring pad width on the 78-79 is 31.5", and on the later Dana 60, it's 36.5".I still don't get what makes the 78-79 the best choice. What makes these years better than those that bolt up more easily?