Let us also keep in mind that shortening the rod could potentially be only half of the equation, and will work if the "bottoming out" occurs at the rod withing the damper, furtherest away from the rod/spring end.

However, if the bump-stop interference is at the end where the rod goes in the damper, than the damper body will have to be shortened as well... it just depends on where the 1st-place of interference takes place.