This project sounds awesome, I did have a similar thought once but i'm not brave enough. When it comes to engines, I agree with above about using a 4cyl, what about the 2ltr from a Fiesta ST?

I don't know for sure, but think a Type 9 box is normally mounted longitudinally, but I would assume the Fiesta ST engine & gearbox is mounted latitudinally like earlier ones. Might make things a little easier, providing you could pick the parts up for a decent price.. just a thought.

Best of luck!