Hi Graham,
because the kit is fairly comprehensive there arn't that many donor parts needed. Although the earlier cars used mostly Rover 827 donor parts they now use mostly Ford Mondeo parts. I adapted mine to Honda Legend and Ed Preston has his running a mix of Audi/Ford/Volvo parts. As the car is in continual development it would be best to speak to Chris at Vortex(Phantom)
http://www.vortex-auto.com/index.html for up to date info. If you could get hold of one of the new Ford v6 Ecoboost engine and gearbox drivelines then you would have an ideal setup.
If you need any more info or fancy meeting up send me a P.M. with contact info.
Ken.