TOPBOND

Asking on behalf of someone who has got a 2000 non turbo import, the engine is busted now an he brought a 98 uk non turbo engine but so much of it don't match up, plugs, sensors etc.. After swapping the parts over it won't start an has been told it's because he needs a 99 engine. Is this Wright? If so what is the difference between the 98 an 99 engine?
Thanks