A bit late for footie...

Let joy be unbounded! With the help of a friend, the fault was traced through to a dodgy wire link to the mainbeam footswitch. One new wire later and all is bright again...well as bright as a Series 2a Land Rover headlight is!
Oh and while I was at it, swapped the broken heater out and for the first time in 7years I have a working heater. I'm wearing shorts, so I drove home with warm ankles! Given that she is my daily drive, I made it through all last winter with no heater, so this is practically revolutionary. :-)