Dirty headlight plastic

N/s headlight has a smokey dirty tinge to it. What would get rid of it I may have at home without going to buy something special just now
cif n a buffer n time

or theres a drill sanding/buffing kit from silverline tools thats good. it looks abit scary at first but you hit it with the different stages of sandpaper and water then u put the buffing head on the drill and buff with some buffing/ cutting compound and it xomes up like glass(i need to do mine soon)
we have only ordered from them once and rhey said a minimum order of £100 for the first order so not sure whats what with it, we are planning on ordering from them.again soon but its all knifes n tape measures n hammers n trolleys/sack barrows we order