Thank you all for your responses.
Just to clarify, as I may not have explained this issue correctly in the first post: the noise is only present when the clutch pedal is up (pedal not depressed = clutch engaged); it is most apparent in neutral at a standstill and at tickover; it may still be there when moving but it is hard to tell amongst all the other noises.
I intend to take CBY's advice today and see if the noise smooths out/reduces when I increase the revs in neutral with the clutch pedal out. If it does then it may just be mechanical rattles that may benefit from checking the correct gearbox oil has been used (as per Morgan/Ford recommendations) - or indeed an additive as suggested by the dealer. I will report back my findings on the rev test.
