Umm...lowering the spring plate will not alter the distance between the bottom of the damper and the driveshaft boot...that is fixed.
Saying that, it is a well known issue that a coilover damper tube with an adjuster (protruding) at the bottom will be closer to an STi driveshaft than a WRX one. For example, DMS coilovers have a recessed adjuster to alleviate this.

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