4 to 5 mm of clips under the rubber bumper at the bottom of the shock shaft. Should be 8mm total including the rubber bumper.
It may vary if you mount the shock inside or outside on the arm, not sure just check for no contact between the cvd and outdrive. Add or remove clips as needed front and rear.

Grey clips that came in the shock bag when new in the box. If you didn't get them with your truck, get em... you probably have them, but wanted to point out the obvious.so nothing was missed in interpretation.