Excellent advice from you both, Richard & Rog.
Yes, I intend to use Monty's column switch and the Morgan wiring, so it’s helpful to know the PCB that controls that circuit can be problematic, I assume/pray the circuit does also include a traditional make/break relay so it would be helpful to know where it lives?
Not sure why you would want to do that given the extra wiring Dave, but your call. Remember extra load's will be placed on headlamp and maybe dip switch, assuming you use halogen bulbs for both.
My advice has been based on the assumption you would source and fit the optional front fog switch and use the existing plug and play behind dash connector. This is what MMC would have done if front fogs or spots had been spec'd on new car. If you want to go this route, once you have sorted and wired the lights at the front, you will need to drop the dash. There you should find an unused 8 pin connector with just two wires leading to it, red/orange and wait for it, blue/yellow, and yes have traced this to the front of car
As a test it will do no harm just to jumper these two connections together to simulate simple toggle switch and check to see your fogs light up. Note you will need to have sidelights on first though.
As far as I can see the auxiliary front light wiring/switching doesn't involve anything to do with the PCB Rog mentions or indeed any relay.
