1994 was the change over year from big to small turbo, you see a good mix of small & big turbos on an M plate, early small turbos still had the big mirrors & early badging on the tailgate.
small turbo had a fuel flap instead of a visable cap, it also had a different engine, YBP with oil squirt jets as standard & the head was meant to flow better, different exhaust, inlet manifolds, managment & turbo but most of the running gear was the same.