the housing itself would spread open with tube going back and forth. One of my Dana’s was in a 55 Chevy street car, 350-4 speed 5.86 ratio with a spool, ladder bars. When at track he used a 10” slick and gave no mercy on that car. When I got the rear tubes were bent bad, heated up housing to close the cracks then welded housing and tubes. I cut and sliced tubes till they were straight again, once welded and ground one couldn’t tell it had been abused. It’s now under my 72 Cuda, was a 70 GTX rear. I made up my housing jig a long time ago, easy to check using that. I had bought the rear for the spool-axels to use in my 64 Savoy.