For hawgs method, you cut or pry away the existing spring stub (dremel,etc), then cut the Bobby pin to fit, securing it by peening the new spring in place. Basically crushing it in the groove cut in the hand. For a new hand, just take it out, replace it, then check timing, stoning the top surface of the hand till timing is correct. You tube or search here to do that. Me, I tend to crush little parts, so I buy and stone/retime.