Audi TT headlamp cleaning

[David Ramsbotham]

My pal has just got a 52 plate Audi TT, good car but the headlamps have a very foggy appearance. It’s not condensation inside but more like a coating on the outside of the plastic. Anyone got any ideas how to clean theses plastic covers to restore them to original clear?
Many thanks, David

[petrolfred]

Cheapo Halfords rubbing compound, water and elbow grease!