Hi all,
Finally managed to finish off this install (was out of action with a bad back and those front seats weigh a tonne).
Special thanks to Jeff and Helmuth, for the advice and guidance. After doing some more research I was missing a relay (where Helmuth has bridged using a wire), the relay is a closed circuit cut out relay and is next to the GM. The price from the dealers was £83.51 but I managed to get a used one for much less

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Thanks again people