A ball I might want has size 1 and 3 vacu grips in it. I use regular grips, sizes 5.5 and 5. Would I be able to put those in without plugging, maybe just having to open up the bottom of the hole?

If put in correctly, the bottom of the holes should be 31/32 which is the outside diameter of the grips. The top size is 1 1/32" If you want to try vacu use 4 & 3 1/2 or plug clear to just under the surface and the re-drill 31/32 you will hardly notice the 1/32" plug around the inserts.
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