I am beginning to think things might not all be doom and gloom,
After calming down and leaving the RR alone for a few days I went to have a look at the old girl I found a hose that had blown off around the lpg system. I put that back on and cleaned the engine bay up a bit there seemed to be a lot less oil than I thought originally.
I put 5 liters of water into the header tank and started her up and she was running smoothly and quietly so off I went for a gentle drive I managed maybe a mile before the temp started climbing and the knocking started again. So I gently removed the header cap and topped up the water and went back home.
Today I thought I would have another look for any signs of leaks I topped up with water again and went for a drive gauge sat perfectly in the middle all the time. I can only do 30mph max in Gib but did that for a mile in 1st gear and it refused to overheat. Top hose is hot and can squeeze it and the radiator is hot all over.
Might I be being too hopeful?