The simplest way to get a lower ride height would be to install shorter, stiffer springs. Round track racing supply places like JEGS or Racer's Wholesale would be a good place to look. You might also need to find a different stroke shock absorber to avoid bottoming out on bumps. A lowering block between the trailing arm and the rear axle housing will probably end up with the trailing arm dragging on speed bumps, etc. The ride quality will be somewhere between annoying and terrible because of the lack of weight in the bed.
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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