if i were you, i wouldn't go with those measures, because they vary from cab to cab. remember, back in the days those cabinets were put together quickly to get them out into the arcades as soon as possible, so it didn't matter whether the sideart was put on perfectly. from my (minimal) stencilling experience, the stencils should be applied so that they look perfect and NOT to match the original. both my pac and my joust stencils as well as my centipede sideart are a couple of centimeters off from which their original position - and it looks much better!
i'd position the stencils so that they are in equidistance to the hat! but that's just my two cents