A lot of round track racing rear ends use big steel rings that resemble split shaft collars, with dowel pins that fit holes drilled into the axle tubes to attach sway bars, coilover shock absorbers, 4-link bars, etc. It wouldn't be difficult to fabricate something like that for rear shock mounting points on a big bolt.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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