It's alive again!!
I've got it all plumbed up and I turned the key on the week end. It runs and idles beautifully with the new manifold on it.
I machined up a billet throttle linkage for it that incorporates 2 extra return springs. Its also adjustable so you can quickly change the return spring tension. It's wound out to the max at the moment as the springs are a bit long. I've machined the air cleaner base to take the Intake Air Temp sensor and the breather. The valley plate is an LS6 item and I've changed it slightly to make the PCV connection a bit neater.
Every thing that the factory manifold has plumbed or connected is there. The Carbon canister vent runs off the side of the manifold back to the purge valve mounted in the tunnel. The MAP sensor is connected to a vacume port off the back of the throttle body.
All I've got left to do is re route the wiring and shorten some of it but I don't want to do this till I've got an answer from the Engineer.
Very happy with the results so far.
Cheers