I think Ray is pulling your leg. Everone knows you'd need 8 holes for that.
Anyway, my truck also has those holes. They look stock, two on each side, right behind the visors. Could they be access holes for a screw driver? Does the headliner fasten there? My truck doesn't have a headliner and I have no idea how it's fastened at the front.
My truck came from Outlook, Saskatchewan. Maybe it's a Saskatchewan thing.