Well, a big thanks to Acsi for popping one in the post for me.
Here is what spiked my interest - I dug up some old snaps from last century. Judging by the date on the back of the photos these were taken at the 1999 Sound of Thunder meeting at Ruapuna. The great thing about the Britten camp is that you could freely walk around their pit and take as many pics as you wanted. They were a little more guarded in the workshop on Carlyle Street, but from time to time they let me take one.



So between races they would be tweaking the ECU management computer and analysing the previous run - there was a red button on the left hand grip where the rider could place markers in the data log when he wanted something checked.
When I went to the John Britten memorial early last year I had a quick chat to the new US owner of the CR&S "Black Beauty" bike, and he mentioned that they had managed to find a laptop "That could run DOS and talk to the bike". Really, any USB/serial interface and terminal would probably work, but I smiled and nodded

Thanks again Acsi - if I can't get it running, it will at least be a great prop next to my two pewter models.