Hi guys,my howling diff saga now has an end.
Took the car back up to Revolutions in Perth where Paul the head technician and myself took the car for an exploratory test drive.Paul agreed that there certainly was a problem and "you could play a tune on it using the throttle.
I left my Morgan with them for investigation.
They identified the problem and shipped the back axle down to a specialist in the Blackpool area for a rebuild.
The axle was returned,rebuilt with a new crown wheel and pinion then refitted back in the car.
Travelled back up to Perth on Wednesday to collect my Sport and then drove home in a transformed car.
Top marks to Elliot,Angus and Paul for sorting this for me and if you need good old fashioned service I highly recommend Revolutions.