Left light unit completely dead

[56 Spider]

Thanks for the help, apart from particlewave's comment - perhaps he had had a bad day. Most responders are usually very helpful to beginners on the forum.

I got the light unit back in OK, although it took a few tries. The over-centre locking mechanism seemed to be jamming up, the unit needed a firm push rear wards before it would lock properly. And yes, there is a good U-tube video that helped. The unit is now working fine.