Please, can someone answer this question for me, I have searched this forum and the i-club and I can not find a straight answer to this simple question. I need to know what the head size is of the oil drain plug with the factory oil temp sensor in it?? It is very large, I read something on i-club about it possibly being 27mm but no one could confirm this. All I need to do is change my oil, why can't anything be easy?