your asking a lot for sails of that age. They were gone 20 years ago. You need to flatten the main in higher wind ranges. Halyard, outhaul, then boom vang to flatten the leach. All that being said if the sail is shot, most likely, you won't be able to get it flat anymore and the draft will have moved back in the sail. It won't be able to do much more than drive you sideways.
S/V Deja Vu