I just got some bench dogs for the MFT top but they are fitting a little loose. My caliper says my (new) MFT holes are 20.12mm and my (old) MFT is only 19.95mm yet my bench dogs are undersized at 19.84mm. Is this right, or is my caliper off? I have seen many other posts that say the holes are 20mm. I am just curious, what should the exact diameter of the MFT holes be? Thanks.