Smudge,
Thanks for the picture. I was wondering if the road middle right, which comes down and sweeps round the end of the runway actualy carried straight on and crosses the light patch of ground before crossing the taxiway was how the road was at that time. There is definitely a line on your photo to support this view. It's 30 years ago now and we were only there a week and - ahem - had other things on our minds at the time.
Perhaps my memory is fading a bit.
What I do remember was that we came across the "Main terminal" for the flights to Glasgow. It was a portacabin with a Loganair aircraft parked outside. The "security" was a plastic chain-link fence that I could have just stepped over! While we were there the pilot and passengers came out of this portacabin and got on board. The one and only ground staff lady then came out, locked the portacabin door, and the pilot said, "Bye Morag. See you tomorrow." then opened the front door of the aircraft, climbed in, started the engine and left! Flying as it used to be!