Have you considered fishing for these screw holes with a sewing needle? If the headliner is put up right, I would go to some trouble before taking it down.
At sun visors, if you can find the first hole the other 2 will come. They aren't in a perfect triangle which does make it more fun.
Screw holes for dome lamp, both in the forward flange of the roof beam. You might need a fish tape to conquer the dome lamp wiring. I have used a speedometer cable for a fish tape. With a little luck the dome lamp wire will be there in the cavity of the roof beam where its belongs.
I never reinstalled the coat hooks but I know they are at a bump out in the metal about 3 inches rear of the shoulder belt bolts. The shoulder belt bolts right above where side glasses meet.
