Changed the spark plugs and air filter on the discovery in preparation for the imminent MOT. Tried again to get the lambda sensor out but it will not budge at all. Apparently you can get a special socket to undo them, which is like a deep socket but with a cut out so that the cable can be passed through. Don't really want to go to the trouble of buying one; plan is to ask the MOT garage to change it if the emissions fail again.
The voltage regulator for the Volvo arrived. Fitted in less than a minute and the charging circuit has been checked and proved correct. Digital camera has arrived (£25 for a 3.2 mega pixel Kodak camera)
Still no work done on the Locost...