Squarring the Rear-End after Spring Install?

THIS------------I've seen documentation on this perhaps the chassis book, don't remember.
That Chassis manual by DC was my Bible back in the day. I have several still today. I offered them on this site a while back when I was sick. My son took some of them for himself. The rest are here in a box somewhere. My wife got tied of moving them after I brought some in for pictures to sell. No one wanted to buy them all. They just wanted to pick what they wanted. So I never sold any. Then I got real sick. Now who knows what box they are in.

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