Foglight lens issue
 

The glass lens on one of my 2001 XKR foglights is no longer clear and has turned a miky white. Has this happened to anyone else?

Is a replacement of the whole assembly is the only option?

unless you can 'clean' the haze from the lens (try buffing it out), then yes, the whole assembly will need to be replaced. Its a DIY job and you can access the mounting points from the fenderwell access cover facing the lights.