I cleaned up all the oil as best I could , took it for a drive and luckily no drips so it could have been 10 years worth of dripping.
carried out an oil change as the oil smelled really bad, also put a new set of iridium plugs in, found a few of the aluminium coil bolts had been sheared off in the head. so there was nothing holding them in, managed to extract the sheared studs and fitted temporary bolts.
the engine now seems a lot quieter , but I think the Powerflex inserts are transmitting some engine vibration, may run it with out to see if that is that cause.
I think the main cause of noise was the loose hydraulic PDCC pipes touching the body work.
still have to change the thermostat , just arrived today.
now finding when it rains the GTS fogs up badly, I am assuming it s the engine not getting warm, or could be damp in the cabin, will need to check under the carpets.
the engine is not running as smoothly as you would expect a big V8 too, but until the stat is replaced there is no point fault finding yet.
also finding the throttle response lagging, if you blip the throttle it stutters then picks up, but the fuel trims could be all over the place with the cool engine.
but generally impressed with the mechanical engineering design, not too impressed with the electrical standard, cheap plugs stretched looms , exposed wires etc but I am an electrical design engineer so more sceptical.