On my 2002 Plus8 the rear fog lens simply screws off like a jamjar lid.
There are 2 dummy screw holes with inserts to seal them, making them look similar to the front and rear brake/indicator lenses that have the 2 fixing screws.
No idea why there is a difference but it is easier to remove/refit the foglight lens, no fiddly screws with top hat receivers!
I have smeared the lens thread with some vaseline to help seal it and prevent moisture getting in.
