My 2011 Vitz

[ezhacker1]

9K/9k Stance 6in springs.

yeah keep preload to a bare minimum, least for the front. The rears, actually you cant preload it, because moving the strut body just moves amount of shaft travel. But still you can bust a strut .

You cant get any more lower/higher than what the springs/ spring perch / lock rings give you or lack there of. So trying to thread that rear strut lower, wont give you more low. The front yeah, the shock body adjusting will control the car height, and not the spring lock ring.