Owenski

my understanding as if it had a light front or rear then it needed the other (ie if you had the back you need a front and vice verses).

Indicators are a seperate issue, if you have them then they are legally required to work. But there is not a legal requirement for you to have them in the first place.

I've not heard the switchgear part before, how could they tell with out stopping you if you had one or not.