It is the lens that I need to seperate from the housing. The clips are off. Now the lens seems sort of stuck to the housing....
The reflector is loose, inside the lens plus housing.
EDIT: I've sorted that now. On the left hand headlamp, someone had used sealant on the rubber seal between the lens and the housing. That probably seemed like a good idea to them at the time. Anyway I have by multi points of gentle leverage persuaded the lens to separate from the housing with no damage.
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