Good morning George , there is a company in the West Midlands (Orson Equipment) who can supply everything you need
http://www.orsonequipment.co.uk/spli..._adaptors.html , I did visit them and actually placed an order but then decided that with the hub adaptor the track would be to wide! from memory WCA bought his from them , you may want to speak to Nick(WCA) for his opinion , the wires do look good but I am more than happy with the Minilites .
I also have a set (Driver/Passenger) glass (rare item)from a Z3 coupe which has a different shape at the rear if your interested? all the best with your build , Geoff .