Hi Dave, thank you for being good enough to take time to take and send these pics. After the weekend settling of the overheating event I have decided to purchase a new top hose and heater control valve and have them fitted. I shall be putting forward to my guardian angel a compression test done and also a cooling system pressure test. Also if possible flow test the rad as well. I think this is the best way forward for now. I've also bought a new radiator expansion tank cap. Thanks again for all you help, regards, Tony.