Postman arrived half an hour ago with the "Erwins" drove the car into the garage and descended into the pit with the 13mm Erwin snug inside a 19mm air impact socket. Couple of whacks with a 5lb hammer, long extension bar and here goes - a sinking feeling as I thought it was slipping but was actually biting deeper into the metal and then it moved - the oil is now draining.
As you can see from the battered state, I tried everything I had including smaller sockets, a cold chisel & lump hammer, even the mig welder. But I don't think it helped being only a 13mm presumably "aftermarket" plug.
Very grateful to Arctic not just for the link but even more value was the trick of using a socket within a socket
I've often cursed my 3/4" set for not having smaller sockets - now I have.
Keep well
