I've found this for sale, which judging by the photos, seems to be an early dash, that has been cut out for a later 2 vent system ?
Waiting on a reply about this from the seller, but that may mean i could do the opposite, and may mean that the later dash structure itself slots in ok on an earlier car ?
Casquette de tableau de bord - Porsche 911 Equipement Auto Paris - leboncoin.fr