After the fire behind the dashboard, the wiring loom has now been changed. My co-driver and I also spent another week or so of trying to figure out why the overdrive wouldn't work! Everything else works properley (well amost! The temperature gauge reads permanently in the red and according to the speedo, we are doing warp factor 9 down side streets!)
The overdrive problem turned out to be where it had been connected the wrong way round at the gearbox end by the previous owner! One this has been resolved, we were back to our 'six gears' instead of four!
Three good doors have also been fitted to replace the ones that were seriously rotten, so I'm just on the look out now for a nearside front one to complete the set. The cars still needs some other TLC to tidy it up bit, but then seeing as there's also a high chance that this car will end up disappearing through a hedge backwards at high speed at some point on the rallies anyway, so why have it in concourse condition ??? :-)