Well....
Picked up a new Speedometer Master Gauge, fitted it and tested it today with a day trip to York.
The problem occurred again so that was a waste of money, I'll now refit the original, I'm quite adept at removing the Dash now.
I'll have a good read of all the recent posts and try as much as I can while the dash is apart, but it will be a small miracle if I find the cause.
I kind of hope that it fails completely soon so that I can give it to a professional to diagnose and fix.
Regards
