Some years ago I had a recommendation of a company to supply a quaife ATB differential fitted and setup in a sierra 7" casing (refurbished of course). I have been over the moon with the service BUT I now want to swap to a 4.44 crownwheel (currently 3.92) I can't find my receipt for the life of me - anyone got any ideas on who I might have used... Road & Race transmission sound vaguely familiar....