Craved - No, the plug does not plug straight in, tried that first - but thanks anyway.
Trust33 - I have brought the proper kit for that model power fc and yes boost is controlled by the handcontroller, but it is the wire from the solenoid that I am trying to work out. The cable is about 100cm, not long enough to go through the firewall unlike the MAP snesor cable whcih plugs into the power fc unit itself.
I am thinking that maybe it is supposed to be rewired and hooked up to the factory solenoid plug....