Do not drive the car with excess oil in the system as this will cause over-pressurisation that can cause problems such as oil tank structural failure. I speak from personal experience!

Agreed! MorganCustom has a venting kit for this that I just installed. About 30 minutes work and the cam chest and oil tank now vent out the pressure. Ran the car until warm, removed the oil cap and put my hand over the opening...quite a bit of pressure in there before.