I had a Morgan 4/4 Sport (2009) for 9 years. I changed the oil sump plug every time during the oil and oil filter change (every 15000kms)..
The original Ford Motor Company (FOMOCO) oil sump plug, purchased in an official Ford dealership garage for the Ford Focus range did not fit right!
Since then, I always used a much cheaper oil sump plug from the aftermarket range for a Ford Focus Sigma engine, which fitted exactly right ( in Belgium).
I never changed the fuel filter ( I drove about 70000km before selling the Morgan).