I have been under the car for three hours cleaning everything trying to confirm where the leak was coming from.
After running the car up to temp 3 times and checking everything, it turns out not to be the crankshaft seal, but the long sump nut weeping.
The one under the big round plug.
I can only assume that the gasket not quite sealing, but as this is internal not worth removing the sump to change the gasket. Instead I undid and removed the bolt, had some oil come out but not too much, cleaned everything and put it back with sealer on the washer and seating face. Hopefully that will stop the leak.
So now have to put it all back together and clean the inevitable fault codes and see how it goes.
I will still pursue the crankshaft tool though as undoubtedly will need one at sometime.