Find the center point of the travel of the shock arm and measure the distance from the end of the shock arm to the suspension mounting point at the axle when the weight is on the wheels. That should be a good starting point for figuring the length needed for the links.
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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