Harry - all i'd say is mk 1 hood even with good seals you don't want to drive distance on motorways with the hood up. I'd take the car or decide between later Aero and 355/360 if that's the gist of the thread. Aero mk3 -Then you'll get better hood and later engine.
ps
Yr 968 sounds interesting, always fancied one of them big 4s (but yours has been souped with a supercharger?)