Well, thanks all for the advice - very much appreciated.
Consensus is that the old EFI Fairlane may not be the best starting point for significant improvements.
I could easily spend similar money on a replacement engine than on what could turn out like open heart surgery on the NC!!!
As Al and Sideshow rightly points out the major problem I have is with the Engine Management System, which I understand is rather inflexible.
I think I will powerchip the NC and see if that provides a 15% power gain the manufacturers infer.
Pete H - Awesome Engine Bay - Looks the business (PM me what EFI parts you have available).
Sppok - Yes a bloody lot of hours (Have you not seen the infrastructure works going on in SE QLD - I'm responsible for it all