All finished now, pretty boring will post some shots though, followed the wiring diagram below (well other than using green in place of yellow wire, as I have none)..

The sound is definitely improved but the actual audio source isn't the highest quality on Dr Who (pre DCS) so can't expect perfection.. The main advantage to me is the subwoofer is now actually a subwoofer and I can adjust its level vs the speakers, that does make a noticeable difference..



Few boring progress shots as I went..