I did adjust the throttle tick over and got it down to 700 RPM.  This made a big difference when driving in traffic on the heat produced by the engine.  The new cylinder head is really helping as well.  I took the car to work in Islington and greatly enjoyed showing it to everyone else.

Whilst the journey home was good because the engine behaved itself the seat became lose and started wobbling around which wasn't.  Turned out that the runner had collapsed.  I sent it back and it was replaced.

I spent a lot of time on the overdrive and started by tracing the wiring loom from the switch to the solenoid.  I discovered that the overdrive actually worked physically pushing the gearbox lever and engaging it which was a good moment.  I removed both relays and checked them and then worked on the throttle switch on the bulkhead.  I had been given some useful instructions on setting up the switch from John at the owners club and realised that the switch was defective.  I ordered a new one but was pretty dismayed by this as it was given to me by another Healey owner many years ago, I was really grateful at the time but now realise that they only did it because it didn't work and was therefore worthless; people are strange.  However, with the new switch installed and the prop shaft disconnected I actually managed to get the overdrive to work which was fantastic.  I had to play about with the settings on the gearbox but it did work and it was a great feeling.  When I tried it on the road it worked beautifully in second gear but not when in third; a new gear selector switch solved this issue.  Now the overdrive works perfectly and it makes a massive difference.  I haven't managed to use the car much since as the weather has been sloppy but it is starting to drive very well.  

The issues are still cropping up but I am getting on top of them.  I had an annoying bang / cracking sounding noise when I went over certain bumps and decided it must be the rod that holds the axel in place because it sits against the axel casing.  I made a few adjustments with this useful tool and it disappeared.

I asked Santa for a hood for Christmas and am hoping that he will be generous.  I have some side screen frames and know where I can get the relevant material required to 'concoct' a set as the usual suppliers all want £600 or thereabouts and I can't stomach that.  The hood probably won't be easy but it will enable me to use the car when the weather is unpredictable and that is a good thing in the UK.  I then need to do the interior which is also a chunk of money but for the moment I am happy with it as it is.  I have a list of little things to see to but the car starts on the button and drives wonderfully.  Oh, and it looks beautiful.