So after much head sctratching I set to it. It was not easy trying to work it out, they seemed to be a sealed unit, not meant to come apart But I was determined, and did it.
Although working out how to put back together was'nt easy either, decided when I do my degree in engineering I would write my thesis on theses stupid things.
Pics show, seperated, cleaned and primed, back together with top coat.