If you say you have a "FEW", try working out a deal with your pro shop for a reduced price on plugging and re-drilling all of them at the same time. But before you do that, go over the current drilling pattern and look at what each ball would do for YOU, if you just plugged the thumb and moved it. If the balls already have finger grips in them and they don't fit, it's only a couple of bucks to get new ones. In fact you can buy a bunch of them and do it yourself and save some money.
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