well did oil and change on ferret today went well getting old filter off bit messy as at first it did now want to leave top housing however new filter went in ok turns out my housing is o ring type as against flat gasket type but fingers crossed and after a ten mile drive no leaks ,tips rags under filter body, if o ring type bit of Vaseline on on o ring helps it stay in place, take off rear deck ,when doing up top bolt keep filter bowl centralised on o ring , fill up filter body with oil ,when ferret fired up oil light went off very quick!