You are better removing the delrin strip by knocking out the pivot pin and not risking spoiling the delrin. While you have it out slightly enlarge the hole in the delrin so that it spins easily after you have thrown the spring away. Attack the pin from the smaller end and really bash it hard and then even harder. Support the arm to keep it still. Easy peasy. Polish the cocking foot to remove all points and edges. Smooth cocking.