I just got my first mould from him with the changeable hollow point pints. Included are about 8 little spring clips that are meant to secure the pins in the mould blocks. They are tiny, and I am having trouble getting them on to seat properly. Does anyone have experience/ tips about how to use them, then remove and reinstall them? Bending them open wider doesn't seem a good plan. How important are they to successful casting with these pins?