where is the bumpstop located and why would it need to be cut?
Bumpstops are inside the strut cover … it slides off after you remove the spring from the strut assembly. With it off, you will see a plate and a foam bumpstop underneath it … you have to tap the plate up with a hammer (gentle) and remove the bumpstop.
You cut them so that the strut does not bottom out with the lowered suspension (bumpstop would hit the strut faster with a lowering spring) … basically allows for the strut to have the same amount of travel as it did before.