OK, I'll drop it and try and weave it into 針孔・めど[.

Seeing that we have a separate めど entry with the meaning "hole", I don't think we should actually have this as a separate entry. I don't think we absolutely have to include 穴/めど anywhere but I don't really see why including it in the 針孔 entry (per daijs) would pose such a big problem. 5/6 readings in that entry already have kanji restrictions, so it wouldn't make the entry much messier than it already is (which really isn't all that messy).

See the discussion within 1254480 and 2159590.