Hi! My car came with Sway-A-Way plates. I want to lower it about a 1/2 inch in the back. Is it really so simple, as to turn the one bolt? What keeps it from rattling losse when driving? Is it supposed to be done with the car on the ground or jacked up? Tried googling and could not find any definitive answers.
Also, whats the rubber cylinder thing around my bolt? (Sorry for all the dirt, I´ve just been driving a lot lately

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