Dear Chris
Glad you are enjoying your Morgan, but sorry you have a problem.
Sudden relay failure is common and you will find either 2 or 3 under the bonnet on the nearside of the car, on the bulkhead area.
I cannot tell you which one it is, but it is worth buying two, replacing them one by one, and then having one as a spare.
It is important to ensure that you get the correct ones for a Morgan, with a diode fitted, to ensure that your battery does not go flat.
Keith at Brands Hatch Morgans will tell you the correct one.
I hope this works
With very best wishes
Michael