Martin. The locking nut is sort of a five pointed star shape, I have the adapter but can't get quite enough purchase on it without forcing it at the wrnog angle (and potentially bending it). The oil pressure sender has been changed, I have the new temp gauge but didn't change it. I like the sense of some sort of capacitor discharge, removing the binacle my be the next step. I am not sure I am brave enough to attempt that this week, firstly becasue there are no guidlines in either of my manuals (see section P indeed), and secondly because I can live with it to get the car to Gaydon. Once there I can demonstrate the problems an hopefully get the full power of the DOC tp help diagnose further! John Chapelhow DOC 19 : 'Boeing' 0737